Post a system message to the affected channel by CLI command (#7877) (#7968)

i18n/en.json

@@ -315,6 +315,14 @@
     "id": "api.channel.leave.left",
     "translation": "%v has left the channel."
   },
+  {
+    "id": "api.channel.change_channel_privacy.private_to_public",
+    "translation": "This channel has been converted to a Public Channel and can be joined by any team member."
+  },
+  {
+    "id": "api.channel.change_channel_privacy.public_to_private",
+    "translation": "This channel has been converted to a Private Channel."
+  },
   {
     "id": "api.channel.post_update_channel_displayname_message_and_forget.create_post.error",
     "translation": "Failed to post displayname update message"