www/grafana: Update 12.2.0 => 12.3.0
Release notes:
https://grafana.com/blog/2025/11/19/grafana-12-3-release-all-the-latest-features/
What's new:
https://grafana.com/docs/grafana/latest/whatsnew/whats-new-in-v12-3/
Changelogs:
https://github.com/grafana/grafana/blob/main/CHANGELOG.md#1230-2025-11-19
PR: 291109
Security: CVE-2025-41115
MFH: 2025Q4
(cherry picked from commit bad451b90fd342f0afcd9453f6a967e8754f3b63)