Remove extra translation that is not used.

i18n/en.i18n.json

@@ -511,8 +511,6 @@
   "unassign-member": "Unassign member",
   "unsaved-description": "You have an unsaved description.",
   "unwatch": "Unwatch",
-  "url-when-custom-login-logo-clicked": "URL when Custom Login Logo clicked",
-  "url-when-custom-top-left-corner-logo-clicked": "URL when Custom Top Left Corner Logo clicked",
   "upload": "Upload",
   "upload-avatar": "Upload an avatar",
   "uploaded-avatar": "Uploaded an avatar",