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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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 58.37%. Comparing base (3a1f33e) to head (6256ca3).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #60   +/-   ##
=======================================
  Coverage   58.37%   58.37%           
=======================================
  Files           4        4           
  Lines         358      358           
=======================================
  Hits          209      209           
  Misses        149      149           

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