Update NmdcPortalApiClient with new authentication scheme

[pkalita-lbl]

Description

The Portal API has replaced session cookie-based authentication with Bearer token authentication. These changes update NmdcPortalApiClient to reflect that.

In testing I also found that the SubmissionPortalTranslator has drifted away from the Portal a bit. In particular, samp_name is now the unique key slot on Biosample instances instead of source_mat_id. These changes also correct that.

Fixes #571

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

• Unit test suite
  • These changes update tests/test_ops/test_data_api_ops.py to reflect the new behavior of NmdcPortalApiClient.
  • These changes fix the test configuration of tests/test_graphs/test_submission_portal_graphs.py and remove the xfail mark.
• Manually ran the translate_metadata_submission_to_nmdc_schema_database job in the Dagit interface

Configuration Details: none

Checklist:

• My code follows the style guidelines of this project (have you run black nmdc_runtime/?)
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (in docs/ and in https://github.com/microbiomedata/NMDC_documentation/?)
• I have added tests that prove my fix is effective or that my feature works, incl. considering downstream usage (e.g. https://github.com/microbiomedata/notebook_hackathons) if applicable.
• New and existing unit and functional tests pass locally with my changes (make up-test && make test-run)

[eecavanna]

Looks good to me!