Add test notification tool (#28334)

* Add test notification tool

* Add frontend styles

* Remove option from admin view

* Refactor create post and add translations

* Fix several CI errors

* Fix API and frontend snapshots

* Refactor trailing and leading icon on buttons

* Add different button states

* i18n-extract

* Fix wrong text

* Add tests

* Fix wrong string

* Fix test

* feat: E2E send test notifications (#28371)

* Refactor send desktop notification

* Address rest of the feedback

* Fix tests

* Add correct link

* Fix test

---------

Co-authored-by: Mattermost Build <build@mattermost.com>
Co-authored-by: yasserfaraazkhan <attitude3cena.yf@gmail.com>

server/channels/app/notification_push.go

@@ -599,6 +599,10 @@ func (a *App) getMobileAppSessions(userID string) ([]*model.Session, *model.AppE
 }
 
 func (a *App) ShouldSendPushNotification(user *model.User, channelNotifyProps model.StringMap, wasMentioned bool, status *model.Status, post *model.Post, isGM bool) bool {
+	if prop := post.GetProp(model.PostPropsForceNotification); prop != nil && prop != "" {
+		return true
+	}
+
 	if notifyPropsAllowedReason := DoesNotifyPropsAllowPushNotification(user, channelNotifyProps, post, wasMentioned, isGM); notifyPropsAllowedReason != "" {
 		a.CountNotificationReason(model.NotificationStatusNotSent, model.NotificationTypePush, notifyPropsAllowedReason, model.NotificationNoPlatform)
 		a.NotificationsLog().Debug("Notification not sent - notify props",