Adapt for 3.11.0

Includes:
- Bump default Java version to 21
- Bump Bazel version to 7.2.1
- Bump Gerrit Docker image to 3.11.0-ubuntu24
- Bump eslint and rollup versions to match 3.11 core
- Bump node version to match 3.11 core (20.14.0)

Release-Notes: Support Gerrit v3.11
Change-Id: I9d2bd09f2582f274ac1d016c238cc7ea7aa183cc
7 files changed