increase minimum asdf and astropy

[braingram]

Bump asdf to 3.3 for #296
Bump astropy to 5.3 per SPEC0

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.39%. Comparing base (add8743) to head (c6ee771).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #297      +/-   ##
==========================================
- Coverage   99.39%   99.39%   -0.01%     
==========================================
  Files          64       64              
  Lines        2330     2325       -5     
==========================================
- Hits         2316     2311       -5     
  Misses         14       14              

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