fix monster relationship field name

Author: pxpm

app/Http/Requests/MonsterRequest.php

@@ -25,7 +25,7 @@ public function rules()
         return [
             'text'            => 'required|min:5|max:255',
             'email'           => 'nullable|email',
-            'dummyicon'       => 'required',
+            'icondummy'       => 'required',
         ];
     }
 
@@ -49,7 +49,7 @@ public function attributes()
     public function messages()
     {
         return [
-            'dummyicon.required' => 'The field "Relationships (all field attributes are guessed)" in #Relationships tab is required.',
+            'icondummy.required' => 'The field "Relationships (all field attributes are guessed)" in #Relationships tab is required.',
         ];
     }
 }