(fix): remove read_elem_partial

[ilan-gold]

• Closes #
• Tests added
• Release note added (or unnecessary)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.75%. Comparing base (3a472c7) to head (39f62ab).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1895      +/-   ##
==========================================
- Coverage   86.47%   84.75%   -1.73%     
==========================================
  Files          45       45              
  Lines        6774     6683      -91     
==========================================
- Hits         5858     5664     -194     
- Misses        916     1019     +103     

Files with missing lines	Coverage Δ
src/anndata/_io/specs/methods.py	95.55% <100.00%> (+5.97%)	⬆️
src/anndata/_io/specs/registry.py	94.18% <ø> (+0.03%)	⬆️

... and 5 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.