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 88.59%. Comparing base (ecc0935) to head (16b9d73).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main      #23   +/-   ##
=========================================
  Coverage     88.59%   88.59%           
  Complexity      671      671           
=========================================
  Files            48       48           
  Lines          1552     1552           
=========================================
  Hits           1375     1375           
  Misses          177      177           

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