avoid error from serverwebroot env var in config.yml
fdroiddata!14158 (merged) introduced env vars to config.yml, which makes very verbose error messages in the checkupdates logs: https://gitlab.com/fdroid/checkupdates-runner/-/jobs/9735257976
fdroiddata!14158 (merged) introduced env vars to config.yml, which makes very verbose error messages in the checkupdates logs: https://gitlab.com/fdroid/checkupdates-runner/-/jobs/9735257976