Fix intermittent SQL logic test failure in limit.slt by adding ORDER BY clause (apache#16257)

* Add order by clause to limit query for consistent results

* test: update explain plan

Author: kosiew

datafusion/sqllogictest/test_files/limit.slt

@@ -835,6 +835,7 @@ explain
 with selection as (
     select *
     from test_limit_with_partitions
+    order by part_key
     limit 1
 )
 select 1 as foo
@@ -847,19 +848,19 @@ logical_plan
 02)--Sort: selection.part_key ASC NULLS LAST, fetch=1000
 03)----Projection: Int64(1) AS foo, selection.part_key
 04)------SubqueryAlias: selection
-05)--------Limit: skip=0, fetch=1
-06)----------TableScan: test_limit_with_partitions projection=[part_key], fetch=1
+05)--------Sort: test_limit_with_partitions.part_key ASC NULLS LAST, fetch=1
+06)----------TableScan: test_limit_with_partitions projection=[part_key]
 physical_plan
-01)ProjectionExec: expr=[foo@0 as foo]
-02)--SortExec: TopK(fetch=1000), expr=[part_key@1 ASC NULLS LAST], preserve_partitioning=[false]
-03)----ProjectionExec: expr=[1 as foo, part_key@0 as part_key]
-04)------CoalescePartitionsExec: fetch=1
-05)--------DataSourceExec: file_groups={3 groups: [[WORKSPACE_ROOT/datafusion/sqllogictest/test_files/scratch/parquet/test_limit_with_partitions/part-0.parquet:0..794], [WORKSPACE_ROOT/datafusion/sqllogictest/test_files/scratch/parquet/test_limit_with_partitions/part-1.parquet:0..794], [WORKSPACE_ROOT/datafusion/sqllogictest/test_files/scratch/parquet/test_limit_with_partitions/part-2.parquet:0..794]]}, projection=[part_key], limit=1, file_type=parquet
+01)ProjectionExec: expr=[1 as foo]
+02)--SortPreservingMergeExec: [part_key@0 ASC NULLS LAST], fetch=1
+03)----SortExec: TopK(fetch=1), expr=[part_key@0 ASC NULLS LAST], preserve_partitioning=[true]
+04)------DataSourceExec: file_groups={3 groups: [[WORKSPACE_ROOT/datafusion/sqllogictest/test_files/scratch/parquet/test_limit_with_partitions/part-0.parquet:0..794], [WORKSPACE_ROOT/datafusion/sqllogictest/test_files/scratch/parquet/test_limit_with_partitions/part-1.parquet:0..794], [WORKSPACE_ROOT/datafusion/sqllogictest/test_files/scratch/parquet/test_limit_with_partitions/part-2.parquet:0..794]]}, projection=[part_key], file_type=parquet
 
 query I
 with selection as (
     select *
     from test_limit_with_partitions
+    order by part_key
     limit 1
 )
 select 1 as foo