fix: add security context to Forgejo runner for Docker socket access

Run the forgejo-runner container as root (uid 0) to allow access to the
Docker socket. This is required for Docker-in-Docker functionality needed
by Forgejo Actions workflows.

Without this, the runner fails with "permission denied" when trying to
access /var/run/docker.sock.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/forgejo-runner/forgejo-runner-deployment.yaml

@@ -18,6 +18,9 @@ spec:
       - name: runner
         image: code.forgejo.org/forgejo/runner:4.0.1
         imagePullPolicy: IfNotPresent
+        securityContext:
+          runAsUser: 0
+          runAsGroup: 0
         command:
         - sh
         - -c