Add cron job for running large tests

[jnwei]

Summary
Creates a cron job for running slow tests that requires GPU or requires the use of a public server. Currently set to run weekly on Wednesdays at 00:00 GMT, we can adjust later to be a different time.

Changes

• Adds an integration tests workflow file
• Changes test_inference_full.py to test an inference job with ColabFold MSAs and template alignments / fetching. Requires both the colabfold public server and RCSB server for template files / information.

Related Issues

• With this setup, the test in tests: query_colabfold_msa_server #145 can be marked as a slow test.

Testing

• Tested integration test manually, which passed.

Other Notes

[jandom]

This looks good, thanks @jnwei