[Feature][Connector-V2][Jdbc] MySQL support read TIMESTAMP_TZ with server_time_zone

[yzeng1618]

https://github.com/apache/seatunnel/issues/9785

Purpose of this pull request

• Add the server_time_zone option to the JDBC source/sink, and thread this option through JdbcConnectionConfig, SimpleJdbcConnectionProvider, and `MysqlDialect. This ensures that the MySQL JDBC driver and row converter use a consistent session time zone, thereby avoiding the 8-hour time difference issue.

• Add TIMESTAMP_TZ read support for MySQL: SeaTunnel TIMESTAMP_TZ is read as OffsetDateTime using the configured server_time_zone (or system default as fallback).

Does this PR introduce any user-facing change?

Yes, but scope is limited:

• MySQL DATETIME mapping is kept as TIMESTAMP (LOCAL_DATE_TIME_TYPE) for backward compatibility.

• MySQL TIMESTAMP columns are now exposed as TIMESTAMP_TZ (OFFSET_DATE_TIME_TYPE) instead of TIMESTAMP to align with timezone-aware semantics and the new server_time_zone option.

• New configuration option server_time_zone is added to JDBC source and sink; when set, it controls both JDBC driver conversion and TIMESTAMP_TZ conversion in the MySQL row converter.

How was this patch tested?

Unit tests:

• Updated MySqlTypeConverterTest to cover DATETIME/TIMESTAMP/TIMESTAMP_TZ mappings.

• Added MysqlJdbcRowConverterTest for TIMESTAMP_TZ reading with system default zone.

• Added SimpleJdbcConnectionProviderTest to verify server_time_zone is correctly translated to the MySQL driver serverTimezone property and not overridden when user sets it explicitly.

E2E:

• Added jdbc_mysql_source_and_sink_server_time_zone.conf and JdbcMysqlIT uses it to validate server_time_zone through real MySQL containers (TIMESTAMP/TIMESTAMP_TZ round trip).

Check list

• [ ] If any new Jar binary package adding in your PR, please add License Notice according New License Guide
• [ * ] If necessary, please update the documentation to describe the new feature. https://github.com/apache/seatunnel/tree/dev/docs
• [ ] If you are contributing the connector code, please check that the following files are updated:
  1. Update plugin-mapping.properties and add new connector information in it
  2. Update the pom file of seatunnel-dist
  3. Add ci label in label-scope-conf
  4. Add e2e testcase in seatunnel-e2e
  5. Update connector plugin_config