[Spark] Add Delta Connect Python Client

[longvu-db]

Which Delta project/connector is this regarding?

• [X] Spark
• [ ] Standalone
• [ ] Flink
• [ ] Kernel
• [ ] Other (fill in here)

Description

This PR adds a basic Python client library for Delta Connect that implements the DeltaTable.forPath, DeltaTable.forName, DeltaTable.toDF and DeltaTable.alias methods. It adds checks to the non-Connect versions of DeltaTable.forPath and DeltaTable.forName to detect the usage of a remote spark session, and to delegate to the Connect versions of these methods.

How was this patch tested?

Reused the existing tests for DeltaTable in test_deltatable.py.

Does this PR introduce any user-facing changes?

No.