Prevent creation of duplicate migration file

In the event of a user erroneously running the rateable:migration command multiple times, prevent creation if the file already exists with a different timestamp

src/commands/MigrationCommand.php

@@ -63,7 +63,9 @@ protected function createMigration()
     {
         $migration_file = database_path('migrations').'/'.date('Y_m_d_His').'_create_ratings_table.php';
 
-        if (! file_exists($migration_file) && $fs = fopen($migration_file, 'x')) {
+        $existing = glob(database_path('migrations').'/*_create_ratings_table.php');
+
+        if (empty($existing) && $fs = fopen($migration_file, 'x')) {
             fwrite($fs, file_get_contents(__DIR__.'/../migrations/create_ratings_table.php'));
             fclose($fs);
             return true;