fix(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

• url-helper.ts now leverages well-known environment variables by @​jww3 in #​1941
• Expand unit test coverage for isGhes by @​jww3 in #​1946

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (60e1cc0) 51.51% compared to head (1efcff7) 51.51%.

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Additional details and impacted files

@@           Coverage Diff           @@
##              dev      #81   +/-   ##
=======================================
  Coverage   51.51%   51.51%           
=======================================
  Files           2        2           
  Lines         860      860           
  Branches      141      141           
=======================================
  Hits          443      443           
  Misses        348      348           
  Partials       69       69           

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