Replace claim plugin

Replaces the claim plugin by fourjr to my claim plugin due to being fundamentally broken as of the current time. It has been created few support issues already that were not successfull  to use the plugin.

Author: martinbndr

plugins/registry.json

@@ -63,13 +63,13 @@
         "thumbnail_url": "https://i.imgur.com/Mo60CdK.png"
     },
     "claim": {
-        "repository": "fourjr/modmail-plugins",
-        "branch": "v4",
-        "description": "Allows supporters to claim thread by sending ?claim in the thread channel",
-        "bot_version": "4.0.0",
+        "repository": "martinbndr/kyb3r-modmail-plugins",
+        "branch": "master",
+        "description": "Adds claim functionality to your modmail bot.",
+        "bot_version": "4.2.1",
         "title": "Claim Thread",
-        "icon_url": "https://i.imgur.com/Mo60CdK.png",
-        "thumbnail_url": "https://i.imgur.com/Mo60CdK.png"
+        "icon_url": "https://i.ibb.co/dsPjgKLj/87249157.png",
+        "thumbnail_url": "https://i.ibb.co/dsPjgKLj/87249157.png"
     },
     "emote-manager": {
         "repository": "fourjr/modmail-plugins",