Document: support JDBC connector besides native SQL Server sink connectors

[Copilot]

Description

added JDBC connector as an additional option alongside the existing native connector

Related code PR

risingwavelabs/risingwave#23416

Related doc issue

Fix #740

Checklist

• I have run the documentation build locally to verify the updates are applied correctly.
• For new pages, I have updated mint.json to include the page in the table of contents.
• All links and references have been checked and are not broken.

[WanYixian]

@copilot We didn’t replace connector='sqlserver' with connector='jdbc'. Instead, we added connector='jdbc' as an additional option because it offers better performance. Update the documentation accordingly.

[Copilot]

@copilot We didn’t replace connector='sqlserver' with connector='jdbc'. Instead, we added connector='jdbc' as an additional option because it offers better performance. Update the documentation acco...

Updated the documentation to include both connector options. The JDBC connector (connector='jdbc') is now documented as the recommended option with better performance, while the native SQL Server connector (connector='sqlserver') is still documented as available. Both connector types now have separate parameter tables and examples. (commit d980767)