chore(deps): 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

📅 Schedule: Branch creation - "before 3am on the first day of the month" (UTC), Automerge - At any time (no schedule defined).

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.28%. Comparing base (9bc334a) to head (473c16a).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #86   +/-   ##
=======================================
  Coverage   95.28%   95.28%           
=======================================
  Files           9        9           
  Lines        1931     1931           
  Branches      162      162           
=======================================
  Hits         1840     1840           
  Misses         91       91           

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