CI: Add Ubuntu24.04 workflow with test matrix support

This commit introduces a new GitHub Actions workflow for building and
testing Apache Cloudberry on Ubuntu 24.04, enabling automated builds,
DEB packaging, and regresssion testing.

Triggers:
- Push to main branch
- Pull requests modifying this workflow file
- Scheduled: Every Monday at 02:00 UTC
- Manual workflow dispatch with optional test selection

Author: tuhaihe