chore(deps): 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

Merging #106 (b555572) into main (2fa8c4f) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##              main      #106   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            5         5           
  Lines           95        95           
  Branches        13        13           
=========================================
  Hits            95        95           

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