[Backport r0.8] Update macos build version

[bot-of-gabrieldemarmiesse]

Backport 4499d71 from #1110

[googlebot]

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[gabrieldemarmiesse]

I'm so proud of my bot 😭

[gabrieldemarmiesse]

Godspeed, little one!

[gabrieldemarmiesse]

It seems that github actions doesn't like when we restart those tests...

[gabrieldemarmiesse]

We need to upgrade our action/checkout to v2 -> actions/checkout#23

[seanpmorgan]

Thanks @bot-of-gabrieldemarmiesse !! Congrats on your first PR 😆