repo: fix bad typing_extensions interaction

[tigarmo]

Ref: https://github.com/pydantic/pydantic/issues/5821#issuecomment-1559196859 We could also pin typing_extensions to 4.5.0 instead, but those pins have a tendency of sticking around.

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[codecov[bot]]

Codecov Report

Merging #78 (fcaf90f) into main (fd9fac8) will increase coverage by 0.01%. The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main      #78      +/-   ##
==========================================
+ Coverage   88.09%   88.11%   +0.01%     
==========================================
  Files          13       13              
  Lines         630      631       +1     
  Branches      125      125              
==========================================
+ Hits          555      556       +1     
  Misses         61       61              
  Partials       14       14              

Impacted Files	Coverage Δ
craft_archives/repo/package_repository.py	98.76% <100.00%> (+<0.01%)	:arrow_up:

[tigarmo]

@lengau sure, done! Might have gone overboard with the comment maybe heh