Update actions/checkout action to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v4 → v6

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Release Notes

actions/checkout (actions/checkout)

v6

Compare Source

v5

Compare Source

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Configuration

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 77.28%. Comparing base (c6dc8de) to head (98bb82c).

Additional details and impacted files

@@            Coverage Diff            @@
##               main      #45   +/-   ##
=========================================
  Coverage     77.28%   77.28%           
  Complexity      313      313           
=========================================
  Files            31       31           
  Lines          1061     1061           
  Branches        134      134           
=========================================
  Hits            820      820           
  Misses          163      163           
  Partials         78       78           

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