Description

Please provide a description of your changes:
fabric_data_source.py — Three changes to the Fabric data source:

1. Added an Optional[DataSourceConnection] parameter to FabricDataSourceImpl.__init__ to match the parent signature
2. Added is_same_soda_data_type_with_synonyms to FabricSqlDialect — treats TIMESTAMP and VARCHAR as equivalent because the Fabric cursor doesn't distinguish between varchar and datetime2 on empty query results.
3. Removed an encode_string_for_sql call in _build_insert_into_values_row_sql to fix an issue with newlines.

fabric_data_source_test_helper.py: drop_schema_if_exists now drops all views and tables in a schema before dropping the schema itself, since SQL Server/Fabric doesn't support CASCADE

Checklist

• I added a test to verify the new functionality.
  • Not required
• I verified this PR does not break soda-extensions.
  • https://github.com/sodadata/soda-extensions/pull/273