Update actions/checkout action to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v5 → v6

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Release Notes

actions/checkout (actions/checkout)

v6

Compare Source

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Configuration

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🚦 Automerge: Enabled.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.53%. Comparing base (c52a562) to head (e20558d).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #112   +/-   ##
=======================================
  Coverage   93.53%   93.53%           
=======================================
  Files           3        3           
  Lines         325      325           
=======================================
  Hits          304      304           
  Misses         21       21           

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