Use the first module name as the group name as default

Modules/Workshop/Scaffold/Module/Generators/EntityGenerator.php

@@ -228,11 +228,11 @@ class EntityGenerator extends Generator
     private function generateSidebarExtender($entities)
     {
         if (count($entities) > 0) {
-            $firstName = $entities[0];
+            $firstModuleName = $entities[0];
 
             return $this->writeFile(
                 $this->getModulesPath('Sidebar/SidebarExtender'),
-                $this->getContentForStub('sidebar-extender.stub', $firstName)
+                $this->getContentForStub('sidebar-extender.stub', $firstModuleName)
             );
         }