deps(renovate): 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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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.01%. Comparing base (2697520) to head (d5c32c2).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #422   +/-   ##
=======================================
  Coverage   97.01%   97.01%           
=======================================
  Files          45       45           
  Lines        2144     2144           
  Branches      212      212           
=======================================
  Hits         2080     2080           
  Misses         64       64           

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