MM-56929- Dont allow guests to be set via team API (#26286)

* dont allow guests to be set via team API

* comment out invalid test

* Update import_functions_test.go

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

server/i18n/en.json

@@ -3162,14 +3162,14 @@
     "id": "api.team.update_team_member_roles.guest.app_error",
     "translation": "Invalid team member update: A guest cannot be made team member or team admin, please promote as a user first."
   },
-  {
-    "id": "api.team.update_team_member_roles.guest_and_admin.app_error",
-    "translation": "Invalid team member update: A user must cannot be set as a guest and admin at the same time."
-  },
   {
     "id": "api.team.update_team_member_roles.guest_and_user.app_error",
     "translation": "Invalid team member update: A user must be a guest or a user but not both."
   },
+  {
+    "id": "api.team.update_team_member_roles.user_and_guest.app_error",
+    "translation": "Invalid team member update: A guest cannot be set for a single team, a System Admin must promote or demote users to/from guests."
+  },
   {
     "id": "api.team.update_team_scheme.license.error",
     "translation": "Your license does not support updating a team's scheme"