[FLINK-31691][table] Add built-in MAP_FROM_ENTRIES function.

[liuyongvs]

• What is the purpose of the change
  This is an implementation of MAP_FROM_ENTRIES

• Brief change log
  MAP_FROM_ENTRIES for Table API and SQL

map_from_entries(map) - Returns a map created from an arrays of row with two fields. Note that the number of fields in a row array should be 2 and the key of a row array should not be null.

Syntax:
  map_from_entries(array_of_rows)

Arguments:
  array_of_rows: an arrays of row with two fields.

Returns:
  Returns a map created from an arrays of row with two fields. Note that the number of fields in a row array should be 2 and the key of a row array should not be null. Returns null if the argument is null

> SELECT map_from_entries(map[1, 'a', 2, 'b']);
 [(1,"a"),(2,"b")]

See also
presto https://prestodb.io/docs/current/functions/map.html

spark https://spark.apache.org/docs/latest/api/sql/index.html#map_from_entries

• Verifying this change
  This change added tests in MapFunctionITCase.

• Does this pull request potentially affect one of the following parts:
  Dependencies (does it add or upgrade a dependency): ( no)
  The public API, i.e., is any changed class annotated with @public(Evolving): (yes )
  The serializers: (no)
  The runtime per-record code paths (performance sensitive): ( no)
  Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: ( no)
  The S3 file system connector: ( no)

• Documentation
  Does this pull request introduce a new feature? (yes)
  If yes, how is the feature documented? (docs)

[flinkbot]

CI report:

• b299bcd Azure: SUCCESS

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[davidradl]

I am wondering what the constrains are for this

• what is the behaviour for duplicate keys - this should be documented, I assume we take the first key value or error. We should add tests for this.
• are there any constraints on the key type - this should be documented and tests added. How would it fail is the key type was not a valid one - for example I would think a nested row is not appropriate for a key, but primitives excluding boolean would seems reasonable.
• • do we check that the rows are of the same shape - we should test how/if this fails and document ?