[SPARK-49226][SQL] Clean-up UDF code generation

### What changes were proposed in this pull request?
This PR reduces the size of code generated for UDFs.

### Why are the changes needed?
Simplification and code reduction.

### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
Existing tests.

### Was this patch authored or co-authored using generative AI tooling?
No

Closes #47746 from hvanhovell/SPARK-49226.

Authored-by: Herman van Hovell <[email protected]>
Signed-off-by: Herman van Hovell <[email protected]>

Author: hvanhovell

connector/connect/client/jvm/src/test/scala/org/apache/spark/sql/connect/client/CheckConnectJvmClientCompatibility.scala

@@ -196,7 +196,6 @@ object CheckConnectJvmClientCompatibility {
       ProblemFilters.exclude[MissingClassProblem](
         "org.apache.spark.sql.ExtendedExplainGenerator"),
       ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.sql.UDTFRegistration"),
-      ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.sql.UDFRegistration$"),
       ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.sql.DataSourceRegistration"),
 
       // DataFrame Reader & Writer
@@ -297,6 +296,10 @@ object CheckConnectJvmClientCompatibility {
       ProblemFilters.exclude[MissingClassProblem](
         "org.apache.spark.sql.artifact.util.ArtifactUtils$"),
 
+      // UDFRegistration
+      ProblemFilters.exclude[DirectMissingMethodProblem](
+        "org.apache.spark.sql.UDFRegistration.register"),
+
       // Datasource V2 partition transforms
       ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.sql.PartitionTransform"),
       ProblemFilters.exclude[MissingClassProblem]("org.apache.spark.sql.PartitionTransform$"),