fix tests.yml (#2688)

### What problem does this PR solve?

fix tests.yml

### Type of change

- [ ] Bug Fix (non-breaking change which fixes an issue)
- [ ] New Feature (non-breaking change which adds functionality)
- [ ] Documentation Update
- [ ] Refactoring
- [ ] Performance Improvement
- [x] Other (please describe):
CI

.github/workflows/tests.yml

@@ -48,7 +48,7 @@ jobs:
       - name: Build ragflow:dev-slim
         run: |
           RUNNER_WORKSPACE_PREFIX=${RUNNER_WORKSPACE_PREFIX:-$HOME}
-          ln -s ${RUNNER_WORKSPACE_PREFIX}/huggingface.co huggingface.co
+          cp -r ${RUNNER_WORKSPACE_PREFIX}/huggingface.co .
           sudo docker build -f Dockerfile.slim -t infiniflow/ragflow:dev-slim .
 
       - name: Build ragflow:dev