FIX: Badge granting recursion error (#20750)

Moving the `grantBadge` action out of the actions hash caused it to clash with a method of the same name from the GrantBadgeController mixin. This commit renames the action.

app/assets/javascripts/admin/addon/controllers/admin-user-badges.js

@@ -69,7 +69,7 @@ export default class AdminUserBadgesController extends Controller.extend(
   }
 
   @action
-  grantBadge() {
+  performGrantBadge() {
     this.grantBadge(
       this.selectedBadgeId,
       this.get("user.username"),

app/assets/javascripts/admin/addon/templates/user-badges.hbs

@@ -34,7 +34,7 @@
         </div>
         <DButton
           @class="btn-primary"
-          @action={{action "grantBadge"}}
+          @action={{this.performGrantBadge}}
           @type="submit"
           @label="admin.badges.grant"
         />