Fix test-cockroach workflow (#2269)

The image has already specified the entrypoint so we don't need to call `/cockroach/cockroach` in `cmd`.
![image](/attachments/669496c1-5673-4609-abc7-f42846e4d479)

Reviewed-on: https://gitea.com/xorm/xorm/pulls/2269
Co-authored-by: Zettat123 <zettat123@gmail.com>
Co-committed-by: Zettat123 <zettat123@gmail.com>

.gitea/workflows/test-cockroach.yml

@@ -51,6 +51,5 @@ jobs:
         ports:
           - 26257:26257
         cmd:
-          - '/cockroach/cockroach'
           - 'start'
           - '--insecure'