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 77.08%. Comparing base (138634e) to head (9690bd9).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #233   +/-   ##
=======================================
  Coverage   77.08%   77.08%           
=======================================
  Files          13       13           
  Lines        1920     1920           
=======================================
  Hits         1480     1480           
  Misses        440      440           

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