Fix early exit from foreach in JForm::removeGroup

The method is supposed to remove all instances of <fields> element but it exits the loop on first iteration only. Looks like a quick copy-paste from removeField may have caused this.

libraries/joomla/form/form.php

@@ -916,11 +916,9 @@ public function removeGroup($group)
 		{
 			$dom = dom_import_simplexml($element);
 			$dom->parentNode->removeChild($dom);
-
-			return true;
 		}
 
-		return false;
+		return true;
 	}
 
 	/**