Update actions/checkout action to v3

[renovate[bot]]

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`](https://togithub.com/actions/checkout/compare/v2...v3) [Compare Source](https://togithub.com/actions/checkout/compare/v2...v3)

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Configuration

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[codecov[bot]]

Codecov Report

Merging #190 (3e66ba3) into master (5114b32) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #190   +/-   ##
=======================================
  Coverage   98.11%   98.11%           
=======================================
  Files           2        2           
  Lines          53       53           
  Branches        5        5           
=======================================
  Hits           52       52           
  Misses          1        1           

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