chore: add exclude for phpcpd

Author: kenjis

.github/workflows/phpcpd.yml

@@ -33,4 +33,4 @@ jobs:
           coverage: none
 
       - name: Detect duplicate code
-        run: phpcpd src/ tests/
+        run: phpcpd src/ tests/ --exclude src/Database/Migrations/2020-12-28-223112_create_auth_tables.php