[SPARK-40775][SQL] Fix duplicate description entries for V2 file scans

### What changes were proposed in this pull request?

Remove overriding the description method in the V2 file sources. `FileScan` already uses all the metadata to create the description, so adding the same fields to the overridden description creates duplicates.

### Why are the changes needed?

Example parquet scan from the agg pushdown suite:

Before:
```
+- BatchScan parquet file:/...[min(_3)#814, max(_3)#815, min(_1)#816, max(_1)#817, count(*)#818L, count(_1)#819L, count(_2)#820L, count(_3)#821L] ParquetScan DataFilters: [], Format: parquet, Location: InMemoryFileIndex(1 paths)[file:/..., PartitionFilters: [], PushedAggregation: [MIN(_3), MAX(_3), MIN(_1), MAX(_1), COUNT(*), COUNT(_1), COUNT(_2), COUNT(_3)], PushedFilters: [], PushedGroupBy: [], ReadSchema: struct<min(_3):int,max(_3):int,min(_1):int,max(_1):int,count(*):bigint,count(_1):bigint,count(_2)..., PushedFilters: [], PushedAggregation: [MIN(_3), MAX(_3), MIN(_1), MAX(_1), COUNT(*), COUNT(_1), COUNT(_2), COUNT(_3)], PushedGroupBy: [] RuntimeFilters: []
```

After:
```
 +- BatchScan parquet file:/...[min(_3)#814, max(_3)#815, min(_1)#816, max(_1)#817, count(*)#818L, count(_1)#819L, count(_2)#820L, count(_3)#821L] ParquetScan DataFilters: [], Format: parquet, Location: InMemoryFileIndex(1 paths)[file:/..., PartitionFilters: [], PushedAggregation: [MIN(_3), MAX(_3), MIN(_1), MAX(_1), COUNT(*), COUNT(_1), COUNT(_2), COUNT(_3)], PushedFilters: [], PushedGroupBy: [], ReadSchema: struct<min(_3):int,max(_3):int,min(_1):int,max(_1):int,count(*):bigint,count(_1):bigint,count(_2)... RuntimeFilters: []
```

### Does this PR introduce _any_ user-facing change?

Just description change in explain output.

### How was this patch tested?

Updated a few UTs to accommodate checking explain string.

Closes #38229 from Kimahriman/remove-file-source-description.

Authored-by: Adam Binford <[email protected]>
Signed-off-by: Wenchen Fan <[email protected]>

Author: Kimahriman

connector/avro/src/main/scala/org/apache/spark/sql/v2/avro/AvroScan.scala

@@ -70,10 +70,6 @@ case class AvroScan(
 
   override def hashCode(): Int = super.hashCode()
 
-  override def description(): String = {
-    super.description() + ", PushedFilters: " + pushedFilters.mkString("[", ", ", "]")
-  }
-
   override def getMetaData(): Map[String, String] = {
     super.getMetaData() ++ Map("PushedFilters" -> seqToString(pushedFilters))
   }

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/v2/csv/CSVScan.scala

@@ -91,10 +91,6 @@ case class CSVScan(
 
   override def hashCode(): Int = super.hashCode()
 
-  override def description(): String = {
-    super.description() + ", PushedFilters: " + pushedFilters.mkString("[", ", ", "]")
-  }
-
   override def getMetaData(): Map[String, String] = {
     super.getMetaData() ++ Map("PushedFilters" -> seqToString(pushedFilters))
   }

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/v2/json/JsonScan.scala

@@ -91,7 +91,7 @@ case class JsonScan(
 
   override def hashCode(): Int = super.hashCode()
 
-  override def description(): String = {
-    super.description() + ", PushedFilters: " + pushedFilters.mkString("[", ", ", "]")
+  override def getMetaData(): Map[String, String] = {
+    super.getMetaData() ++ Map("PushedFilters" -> pushedFilters.mkString("[", ", ", "]"))
   }
 }

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/v2/orc/OrcScan.scala

@@ -92,12 +92,6 @@ case class OrcScan(
     ("[]", "[]")
   }
 
-  override def description(): String = {
-    super.description() + ", PushedFilters: " + seqToString(pushedFilters) +
-      ", PushedAggregation: " + pushedAggregationsStr +
-      ", PushedGroupBy: " + pushedGroupByStr
-  }
-
   override def getMetaData(): Map[String, String] = {
     super.getMetaData() ++ Map("PushedFilters" -> seqToString(pushedFilters)) ++
       Map("PushedAggregation" -> pushedAggregationsStr) ++

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/v2/parquet/ParquetScan.scala

@@ -127,12 +127,6 @@ case class ParquetScan(
     ("[]", "[]")
   }
 
-  override def description(): String = {
-    super.description() + ", PushedFilters: " + seqToString(pushedFilters) +
-      ", PushedAggregation: " + pushedAggregationsStr +
-      ", PushedGroupBy: " + pushedGroupByStr
-  }
-
   override def getMetaData(): Map[String, String] = {
     super.getMetaData() ++ Map("PushedFilters" -> seqToString(pushedFilters)) ++
       Map("PushedAggregation" -> pushedAggregationsStr) ++

sql/core/src/test/scala/org/apache/spark/sql/ExplainSuite.scala

@@ -462,27 +462,18 @@ class ExplainSuite extends ExplainSuiteHelper with DisableAdaptiveExecutionSuite
     withTempDir { dir =>
       Seq("parquet", "orc", "csv", "json").foreach { fmt =>
         val basePath = dir.getCanonicalPath + "/" + fmt
-        val pushFilterMaps = Map (
-          "parquet" ->
-            "|PushedFilters: \\[IsNotNull\\(value\\), GreaterThan\\(value,2\\)\\]",
-          "orc" ->
-            "|PushedFilters: \\[IsNotNull\\(value\\), GreaterThan\\(value,2\\)\\]",
-          "csv" ->
-            "|PushedFilters: \\[IsNotNull\\(value\\), GreaterThan\\(value,2\\)\\]",
-          "json" ->
-            "|remove_marker"
-        )
-        val expected_plan_fragment1 =
+
+        val expectedPlanFragment =
           s"""
              |\\(1\\) BatchScan $fmt file:$basePath
              |Output \\[2\\]: \\[value#x, id#x\\]
              |DataFilters: \\[isnotnull\\(value#x\\), \\(value#x > 2\\)\\]
              |Format: $fmt
              |Location: InMemoryFileIndex\\([0-9]+ paths\\)\\[.*\\]
              |PartitionFilters: \\[isnotnull\\(id#x\\), \\(id#x > 1\\)\\]
-             ${pushFilterMaps.get(fmt).get}
+             |PushedFilters: \\[IsNotNull\\(value\\), GreaterThan\\(value,2\\)\\]
              |ReadSchema: struct\\<value:int\\>
-             |""".stripMargin.replaceAll("\nremove_marker", "").trim
+             |""".stripMargin.trim
 
         spark.range(10)
           .select(col("id"), col("id").as("value"))
@@ -500,7 +491,7 @@ class ExplainSuite extends ExplainSuiteHelper with DisableAdaptiveExecutionSuite
             .format(fmt)
             .load(basePath).where($"id" > 1 && $"value" > 2)
           val normalizedOutput = getNormalizedExplain(df, FormattedMode)
-          assert(expected_plan_fragment1.r.findAllMatchIn(normalizedOutput).length == 1)
+          assert(expectedPlanFragment.r.findAllMatchIn(normalizedOutput).length == 1)
         }
       }
     }

sql/core/src/test/scala/org/apache/spark/sql/execution/datasources/FileSourceAggregatePushDownSuite.scala

@@ -347,7 +347,8 @@ trait FileSourceAggregatePushDownSuite
         spark.read.format(format).load(file.getCanonicalPath).createOrReplaceTempView("test")
         Seq("false", "true").foreach { enableVectorizedReader =>
           withSQLConf(aggPushDownEnabledKey -> "true",
-            vectorizedReaderEnabledKey -> enableVectorizedReader) {
+            vectorizedReaderEnabledKey -> enableVectorizedReader,
+            SQLConf.MAX_METADATA_STRING_LENGTH.key -> "1000") {
 
             val testMinWithAllTypes = sql("SELECT min(StringCol), min(BooleanCol), min(ByteCol), " +
               "min(BinaryCol), min(ShortCol), min(IntegerCol), min(LongCol), min(FloatCol), " +