[MM-45802] Clear CRT notification on deleted reply (#23568)

* reduce the counter on post deletion

* add test

* change translations

* fix collecting mentions for DMs

* add translation texts

* extract logic for getting mentions

* send WS event

* add e2e tests

* tidy mod

* WIP

* Deleting notification async

* Fixed a unit test

* Added more tests

* Updated i18n

* CI

* mattermost-server -> mattermost

* mattermost-server -> mattermost

---------

Co-authored-by: Konstantinos Pittas <konstantinos.pittas@mattermost.com>
Co-authored-by: Mattermost Build <build@mattermost.com>

server/i18n/en.json

@@ -6191,6 +6191,10 @@
     "id": "app.post.delete.app_error",
     "translation": "Unable to delete the post."
   },
+  {
+    "id": "app.post.delete_post.get_team.app_error",
+    "translation": "An error occurred getting the team."
+  },
   {
     "id": "app.post.get.app_error",
     "translation": "Unable to get the post."