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

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Configuration

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[codecov]

Codecov Report

Merging #162 (7714fa3) into master (69c3d4e) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #162   +/-   ##
=======================================
  Coverage   99.25%   99.25%           
=======================================
  Files          24       24           
  Lines        1886     1886           
=======================================
  Hits         1872     1872           
  Misses          9        9           
  Partials        5        5           

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