remove user from a group

src/Domain/User/User.php

@@ -214,11 +214,14 @@ class User implements JsonSerializable
         $this->$password = $password;
     }
     
-    
     public function addGroup(Group $group){
         $this->groups->add($group);
     }
 
+    public function removeGroup(Group $group){
+        $this->groups->removeElement($group);
+    }
+
     public function addAdmin(Group $group){
         $this->admin->add($group);
     }