Add GitHub Action Workflow for CI
Add GitHub Action Workflow for CI

This commit adds a GitHub Actions workflow to replace both CircleCI and
LinuxKit CI.

It will build the Linuxkit binary, run tests and upload artifacts

It replaces the Integration Tests that are run by Linuxkit CI via
the make ci or make ci-pr targets with multiple sets of Integration
Tests that are run in parallel.

It does not yet test GCP. The GCP test in LinuxKit CI could be moved to RTF

Signed-off-by: Dave Tucker <bfcdf3e6ca6cef45543bfbb57509c92aec9a39fb@dtucker.co.uk>

konstruktoid/linuxkit,linuxkit/linuxkit,deitch/linuxkit,JohnnyLeone/linuxkit,konstruktoid/linuxkit,justincormack/linuxkit,justincormack/linuxkit,djs55/linuxkit,furious-luke/linuxkit,deitch/linuxkit,djs55/linuxkit,konstruktoid/linuxkit,rn/linuxkit,JohnnyLeone/linuxkit,deitch/linuxkit,justincormack/linuxkit,linuxkit/linuxkit,deitch/linuxkit,linuxkit/linuxkit,deitch/linuxkit,furious-luke/linuxkit,justincormack/linuxkit,djs55/linuxkit,rn/linuxkit,rn/linuxkit,furious-luke/linuxkit,JohnnyLeone/linuxkit,furious-luke/linuxkit,linuxkit/linuxkit,justincormack/linuxkit,konstruktoid/linuxkit,justincormack/linuxkit,rn/linuxkit,konstruktoid/linuxkit,djs55/linuxkit,djs55/linuxkit,rn/linuxkit,konstruktoid/linuxkit,JohnnyLeone/linuxkit,furious-luke/linuxkit,linuxkit/linuxkit,JohnnyLeone/linuxkit