Reset LegendMetadata instance after checkout

[gipert]

Closes #82.

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 60.04%. Comparing base (14df8ff) to head (54f434b).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
src/legendmeta/core.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #83      +/-   ##
==========================================
+ Coverage   57.40%   60.04%   +2.64%     
==========================================
  Files           8        7       -1     
  Lines         493      453      -40     
==========================================
- Hits          283      272      -11     
+ Misses        210      181      -29     

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