fix(forgejo-runner): revert COMMUNITY_SCRIPTS_URL override per review

Drop the env-var indirection on the build.func source URL; it was a dev
convenience for testing against a fork and adds no user-facing value.

Author: imjustafox

ct/forgejo-runner.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
-source <(curl -fsSL "${COMMUNITY_SCRIPTS_URL:-https://raw.githubusercontent.com/community-scripts/ProxmoxVED/main}/misc/build.func")
+source <(curl -fsSL https://raw.githubusercontent.com/community-scripts/ProxmoxVED/main/misc/build.func)
 
 # Copyright (c) 2021-2026 community-scripts ORG
 # Author: Simon Friedrich