Update actions/checkout action to v3

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v2 -> v3

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Release Notes

actions/checkout

v3

Compare Source

• Update to node 16

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Configuration

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[codecov]

Codecov Report

Merging #10 (d8628af) into master (21ebd9a) will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master     #10   +/-   ##
======================================
  Coverage    1.23%   1.23%           
======================================
  Files           2       2           
  Lines          81      81           
======================================
  Hits            1       1           
  Misses         80      80           

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