Grafana fails with /var/lib/grafana as symlink

### What happened? Upgrading Grafana resulted in crash, saying the grafana.db is locked. Removing the file results in Grafana crash while trying to create it, saying the filesystem is readonly. ### What did you expect to happen? Grafana to be able to write to /var/lib/grafana and grafana.db ### Did this work before? Yes, I believe up to 11.5.x this worked without issues ### How do we reproduce it? 1. `ln -s /opt/some-existing-directory /var/lib/grafana` 2. Make sure grafana user/group have write access to that dir. 3. Start `grafana-server`. ### Is the bug inside a dashboard panel? _No response_ ### Environment (with versions)? Grafana: 12.x OS: RedHat ### Grafana platform? A package manager (APT, YUM, BREW, etc.) ### Datasource(s)? _No response_