Fix status_check_contexts matching bug

[Zettat123]

Fix #28570
Follow #24633

---

Copied from #28570 (comment)

The feature introduced in #24633 should be compatible with status_check_contexts. However, if one or more of status_check_contexts is not a legal glob expressions, glob.Compile will fail and the contexts cannot match.

gitea/routers/web/repo/pull.go

Lines 653 to 663 in 21229ed

	if pb != nil && pb.EnableStatusCheck {
	ctx.Data["is_context_required"] = func(context string) bool {
	for _, c := range pb.StatusCheckContexts {
	if gp, err := glob.Compile(c); err == nil && gp.Match(context) {
	return true
	}
	}
	return false
	}
	ctx.Data["RequiredStatusCheckState"] = pull_service.MergeRequiredContextsCommitStatus(commitStatuses, pb.StatusCheckContexts)
	}