Setup Github Actions for testing release binary against linux and darwin

[gsquared94]

Runs integration tests at 10 AM UTC every day against the release bits of skaffold in ubuntu and macos. Uses minikube instead of kind.

We can later add badges:

[codecov]

Codecov Report

Merging #4300 into master will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #4300   +/-   ##
=======================================
  Coverage   71.91%   71.91%           
=======================================
  Files         322      322           
  Lines       12312    12313    +1     
=======================================
+ Hits         8854     8855    +1     
  Misses       2897     2897           
  Partials      561      561           

Impacted Files	Coverage Δ
pkg/skaffold/build/cluster/pod.go	87.57% <0.00%> (+0.07%)	⬆️

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[briandealwis]

Cool! But why 10am UTC? That’s mid-day for @dgageot!

[briandealwis]

I take it back: 10:00 UTC is brilliant since it's early enough to fix same-day.

[briandealwis]

I'm new to Github Actions so excuse naïve questions. Can we create reuseable scripts with pluggable values? Wondering if we can create parallel tests to verify compatibility with our minimum supported versions.

[nkubala]

very nice, let's follow up and see if we have any options for testing against windows