add can_admin for CustomInventoryScripts

awx/main/access.py

@@ -1384,6 +1384,10 @@ class CustomInventoryScriptAccess(BaseAccess):
             return self.model.objects.distinct().all()
         return self.model.accessible_objects(self.user, 'read_role').all()
 
+    @check_superuser
+    def can_admin(self, obj):
+        return self.user in obj.admin_role
+
     @check_superuser
     def can_read(self, obj):
         return self.user in obj.read_role