chore(deps): update actions/checkout action to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v5 -> v6

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Release Notes

actions/checkout (actions/checkout)

v6

Compare Source

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Configuration

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[codspeed-hq]

CodSpeed Performance Report

Merging #230 will not alter performance

_{Comparing renovate/actions-checkout-6.x (b063f9d) with main (8a8b517)}

Summary

✅ 9 untouched

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.14%. Comparing base (8a8b517) to head (b063f9d).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #230   +/-   ##
=======================================
  Coverage   86.14%   86.14%           
=======================================
  Files           8        8           
  Lines        1314     1314           
  Branches      319      319           
=======================================
  Hits         1132     1132           
  Misses        182      182           

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