Introduce staging tests for the upload test in GitHub

Currently, our CI fails when we try to test `kernels upload ...` as it includes a write operation. 

The plan is to move to a staging environment to conduct this test similar to:
https://github.com/huggingface/diffusers/blob/751e250f70cf446ae342c8a860d92f6a8b78261a/tests/models/test_modeling_common.py#L1945