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 #16 (7f482ad) into master (211f16c) will not change coverage.
Report is 1 commits behind head on master.
The diff coverage is n/a.

❗ Current head 7f482ad differs from pull request most recent head 0c595ea. Consider uploading reports for the commit 0c595ea to get more accurate results

@@           Coverage Diff           @@
##           master      #16   +/-   ##
=======================================
  Coverage   69.02%   69.02%           
=======================================
  Files          17       17           
  Lines         749      749           
=======================================
  Hits          517      517           
  Misses        232      232