[SPARK-3575][SQL] Removes the Metastore Parquet table conversion hack

This PR tries to remove the Metastore Parquet conversion hack by moving the conversion logic to `HiveMetastoreCatalog`, i.e., convert `MetastoreRelation` to `ParquetRelation` when we find that the Hive table is backed by Parquet, and make the converted `ParquetRelation` inherit the original Hive schema. As a side effect, `spark.sql.parquet.binaryAsString` can be removed since Metastore field types are now reserved.

TODO

- [x] Add tests
- [x] Fix partitioning tests failure
- [x] Code cleanup

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Yea, forgot that in case of `MetastoreRelation` partition pruning is done within `HiveTableScan`... I'll add a WIP tag to this PR and add back partition pruning.