Fix cached error when .domains is not readable (fixes https://codeberg.org/Codeberg/Community/issues/1512)

Co-authored-by: @algernon

server/upstream/domains.go

@@ -33,7 +33,8 @@ func (o *Options) CheckCanonicalDomain(giteaClient *gitea.Client, actualDomain,
 	body, err := giteaClient.GiteaRawContent(o.TargetOwner, o.TargetRepo, o.TargetBranch, canonicalDomainConfig)
 	if err != nil && !errors.Is(err, gitea.ErrorNotFound) {
 		log.Error().Err(err).Msgf("could not read %s of %s/%s", canonicalDomainConfig, o.TargetOwner, o.TargetRepo)
-		// TODO: WTF we just continue?! Seems fine as body is empty... :/
+		// Assume that the domain is valid, as Gitea seems to be broken. Don't cache it though.
+		return actualDomain, true
 	}
 
 	var domains []string