Update Snowflake JDBC driver to 4.3.4

[vishwasvaidya-cloudsufi]

Summary

Bumps snowflake-jdbc.version from 4.0.2 to 4.3.4.

Driver 4.0.2 fails to create the S3 client when the stage endpoint has no URI scheme. Snowflake Government accounts return their endpoint this way, so every read (downloadStream) fails on
those accounts with:
java.lang.NullPointerException: The URI scheme of endpointOverride must not be null.
Snowflake fixed this upstream in snowflakedb/snowflake-jdbc#2572 (SNOW-3344317), first released in 4.2.0. In 4.3.4, an endpoint without a scheme gets https:// added before the client is built.
The plugin code needs no changes: the driver APIs it uses (SnowflakeConnection,
UploadStreamConfig, DownloadStreamConfig, SnowflakeBasicDataSource) are the same in 4.3.4.The driver is still built for Java 8, and the CDAP parent range is unchanged, so CDAP 6.10 and 6.11 stay supported.

Changes

• pom.xml: snowflake-jdbc.version 4.0.2 → 4.3.4
• New SnowflakeS3StageEndpointTest: builds the S3 client the same way downloadStream does (StageInfo → StorageClientFactory.createClient) and checks the endpoint it ends up with:
  • endpoint without a scheme → https://<endpoint>
  • https:// endpoint → unchanged
  • no endpoint → no override

Testing

Driver	SnowflakeS3StageEndpointTest
4.0.2	scheme-less case fails with the NPE above; other 2 pass
4.3.4	3/3 pass

[gemini-code-assist]

Code Review

This pull request upgrades the snowflake-jdbc dependency version from 4.0.2 to 4.3.4 in pom.xml. It also introduces a new unit test, SnowflakeS3StageEndpointTest.java, to verify that the S3 client correctly handles and normalizes schemeless stage endpoints returned by Snowflake (such as those from government accounts). I have no feedback to provide as there are no review comments to evaluate.