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 91.93%. Comparing base (6db5988) to head (53e7abd).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #188   +/-   ##
=======================================
  Coverage   91.93%   91.93%           
=======================================
  Files          20       20           
  Lines        1897     1897           
=======================================
  Hits         1744     1744           
  Misses        153      153           

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