upgrade: update actions/checkout action to v4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v3 -> v4

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Release Notes

actions/checkout (actions/checkout)

v4

Compare Source

• Check out other refs/* by commit if provided, fall back to ref by @​orhantoy in https://github.com/actions/checkout/pull/1924

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Configuration

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.55%. Comparing base (209aced) to head (d20c737).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #655   +/-   ##
=======================================
  Coverage   97.55%   97.55%           
=======================================
  Files          21       21           
  Lines         819      819           
=======================================
  Hits          799      799           
  Misses         20       20           

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