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 49.84%. Comparing base (71ffe58) to head (b522051).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #530   +/-   ##
=======================================
  Coverage   49.84%   49.84%           
=======================================
  Files           6        6           
  Lines         331      331           
=======================================
  Hits          165      165           
  Misses        166      166           

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