Alerting: Time interval Delete API to check for usages in alert rules (#90500)

* Check if a time interval is used in alert rules before deleting it
* Add time interval to parameters of ListAlertRulesQuery and ListNotificationSettings of DbStore

== Refacorings == 
* refactor isMuteTimeInUse to accept a single route
* update getMuteTiming to not return err
* update delete to get the mute timing from config first

pkg/services/ngalert/provisioning/testing.go

@@ -217,3 +217,40 @@ func (s *fakeRuleAccessControlService) CanWriteAllRules(ctx context.Context, use
 	}
 	return false, nil
 }
+
+type fakeAlertRuleNotificationStore struct {
+	Calls []call
+
+	RenameReceiverInNotificationSettingsFn func(ctx context.Context, orgID int64, oldReceiver, newReceiver string) (int, error)
+	ListNotificationSettingsFn             func(ctx context.Context, q models.ListNotificationSettingsQuery) (map[models.AlertRuleKey][]models.NotificationSettings, error)
+}
+
+func (f *fakeAlertRuleNotificationStore) RenameReceiverInNotificationSettings(ctx context.Context, orgID int64, oldReceiver, newReceiver string) (int, error) {
+	call := call{
+		Method: "RenameReceiverInNotificationSettings",
+		Args:   []interface{}{ctx, orgID, oldReceiver, newReceiver},
+	}
+	f.Calls = append(f.Calls, call)
+
+	if f.RenameReceiverInNotificationSettingsFn != nil {
+		return f.RenameReceiverInNotificationSettingsFn(ctx, orgID, oldReceiver, newReceiver)
+	}
+
+	// Default values when no function hook is provided
+	return 0, nil
+}
+
+func (f *fakeAlertRuleNotificationStore) ListNotificationSettings(ctx context.Context, q models.ListNotificationSettingsQuery) (map[models.AlertRuleKey][]models.NotificationSettings, error) {
+	call := call{
+		Method: "ListNotificationSettings",
+		Args:   []interface{}{ctx, q},
+	}
+	f.Calls = append(f.Calls, call)
+
+	if f.ListNotificationSettingsFn != nil {
+		return f.ListNotificationSettingsFn(ctx, q)
+	}
+
+	// Default values when no function hook is provided
+	return nil, nil
+}