[MM-20804] Add "Unarchive Channel" option to the channel info screen (#13349)

* add websocket hooks to restoreChannel

* add userId to call in api4

* add constant

* undo changes in en.json

* add constants to en.json

* delete  code for deleting webhooks

* Update i18n/en.json

Co-Authored-By: Ben Schumacher <ben.schumacher@mattermost.com>

* restore channel ordering

* delete Props

* Update app/channel.go

Co-Authored-By: Ben Schumacher <ben.schumacher@mattermost.com>

* Update app/channel.go

Co-Authored-By: Ben Schumacher <ben.schumacher@mattermost.com>

* change message format

* move WS message right after invalidate

* manually reorder en.json entry

* reorder en.json

* undelete to restore

* update en.json ordering

* update wording

* Update model/post.go

Co-Authored-By: Saturnino Abril <saturnino.abril@gmail.com>

* Update model/websocket_message.go

Co-Authored-By: Saturnino Abril <saturnino.abril@gmail.com>

* gofmt

* undeleted to restored

* add test to success case

* delete repeated test

Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>
Co-authored-by: Saturnino Abril <saturnino.abril@gmail.com>
Co-authored-by: mattermod <mattermod@users.noreply.github.com>

i18n/en.json

@@ -367,6 +367,14 @@
     "id": "api.channel.rename_channel.cant_rename_group_messages.app_error",
     "translation": "You cannot rename a group message channel"
   },
+  {
+    "id": "api.channel.restore_channel.restored.app_error",
+    "translation": "Unable to unarchive channel. The channel is not archived."
+  },
+  {
+    "id": "api.channel.restore_channel.unarchived",
+    "translation": "{{.Username}} unarchived the channel."
+  },
   {
     "id": "api.channel.update_channel.deleted.app_error",
     "translation": "The channel has been archived or deleted"