feat: add support for mus musculus descendant organisms

[joyceyan]

Reason for Change

https://app.zenhub.com/workspaces/single-cell-5e2a191dad828d52cc78b028/issues/gh/chanzuckerberg/single-cell-curation/1243

Changes

• updates schema definition to add support for mus musculus descendants
• upon further inspection it appears as if the print output for ONTOLOGY_PARSER.get_term_descendants("NCBITaxon:10090", include_self=True) is simply term_descendants ['NCBITaxon:10090']

Testing

added unit tests to ensure mouse descendant terms are accepted

Notes for Reviewer

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.90%. Comparing base (011bbad) to head (a085ed8).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1248      +/-   ##
==========================================
- Coverage   89.92%   89.90%   -0.02%     
==========================================
  Files          19       19              
  Lines        2193     2200       +7     
==========================================
+ Hits         1972     1978       +6     
- Misses        221      222       +1     

Components	Coverage Δ
cellxgene_schema_cli	90.86% <100.00%> (-0.03%)	⬇️
migration_assistant	91.26% <ø> (ø)
schema_bump_dry_run_genes	79.80% <ø> (ø)
schema_bump_dry_run_ontologies	99.53% <ø> (ø)

[ejmolinelli]

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