The Docker Compose example currently mounts the PostgreSQL data directory to `/var/lib/postgresql/data`.
With PostgreSQL 18, the official PostgreSQL Docker image expects the volume to be mounted at `/var/lib/postgresql` instead. Mounting `/var/lib/postgresql/data` causes the container to fail during startup because the image detects PostgreSQL data at an unused mount point.
This change updates the example to use the recommended `/var/lib/postgresql` mount path for PostgreSQL 18 and newer.
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Co-authored-by: silverwind <[email protected]>
Reviewed-on: https://gitea.com/gitea/docs/pulls/570
Reviewed-by: silverwind <[email protected]>
Co-authored-by: JWheelMaker <[email protected]>