Allow `nmdc_data.py` consumer to specify which variant of schema they want to access

[eecavanna]

Summary of changes

Note: This summary was copied from here.

In this branch, I updated nmdc_data.py so that the fuctions that provide access to the JSON Schema version of the schema, allow the caller to specify which variant of the schema they want (they currently only support the default variant and the nmdc_materialized_patterns variant).

That will allow callers (such as the Runtime and the migration notebooks) to access the nmdc_materialized_patterns.schema.json JSON Schema (which they can use to perform data validation).

I also added doctests to all modified functions to demonstrate that they return values of the types I expect. The doctests can be run via $ poetry run python -m doctest nmdc_schema/nmdc_data.py (or, now, $ make test-python).

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Note for reviewers

• This PR contains the same changes as https://github.com/microbiomedata/berkeley-schema-fy24/pull/204 (in fact, the commits on this branch were git cherry-pick-ed directly from the branch in that PR). This PR is the nmdc-schema equivalent of that berkeley-schema-fy24 PR.
• I tagged the two people that reviewed the berkeley-schema-fy24 PR, as reviewers of this PR. I also tagged someone else that has worked on the nmdc_data.py file in the past.

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Note regarding schema freeze

• This branch does not contain any schema changes.
• This branch does add functionality that is available to downstream things that import the nmdc_data.py script (e.g. the Runtime), but it doesn't break any existing functionality. It is "opt in" functionality.

[github-actions[bot]]

PR Preview Action v1.4.7 :---: :rocket: Deployed preview to https://microbiomedata.github.io/nmdc-schema/pr-preview/pr-2091/ on branch gh-pages at 2024-06-28 06:59 UTC

[mslarae13]

Approved during berk-schema meeting check in. Only change, default should include/ require materialized patterns & you have the option to say no but we will split that out from this PR.