Update to python 3.10. Sync for use by hydrator. Remove a TStreamer assertion.

[sathabbott]

Pushing changes needed for hydrator package dependency.
https://github.com/robjectifier/rhydrator

[codecov-commenter]

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Codecov Report

❌ Patch coverage is 97.87234% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 91.32%. Comparing base (3b6f3d5) to head (1444639).

Files with missing lines	Patch %	Lines
src/rootfilespec/rntuple/schema.py	90.90%	1 Missing ⚠️
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Additional details and impacted files

@@            Coverage Diff             @@
##             main      #54      +/-   ##
==========================================
- Coverage   91.36%   91.32%   -0.04%     
==========================================
  Files          36       36              
  Lines        2723     2722       -1     
==========================================
- Hits         2488     2486       -2     
- Misses        235      236       +1     

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[nsmith-]

I don't see any issues. If you want to break this into a py3.10 migration PR and separately a PR for updating the RNTuple interface that would look cleaner but up to you.