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-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 68.89%. Comparing base (8ea572c) to head (dbd6f32).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #181      +/-   ##
==========================================
- Coverage   68.93%   68.89%   -0.04%     
==========================================
  Files          17       17              
  Lines        2540     2540              
==========================================
- Hits         1751     1750       -1     
- Misses        789      790       +1     

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