[SCB-2199] Add GitHub Actions workflows

[coolbeevip]

• Add a CI workflow for PRs and push branch master

[zhfeng]

Thanks @coolbeevip - Nice work !

Is it possible to remove the travis configration if we make sure github flow works ?

[WillemJiang]

Why we do this if the tests are failed?

[coolbeevip]

After the test fails, the unit test report will be uploaded to Github for easy download through the Github web interface

[WillemJiang]

It makes sense.

[coolbeevip]

Thanks @coolbeevip - Nice work !

Is it possible to remove the travis configration if we make sure github flow works ?

Build and tests passed in my forked repository https://github.com/coolbeevip/servicecomb-pack/actions/runs/612410941
But Sonar and Coverage have not been added yet. I will add sonar and coverage in other PRs and remove the travis config

[zhfeng]

@coolbeevip can you squash all the commits before merging ?

[coolbeevip]

@coolbeevip can you squash all the commits before merging ?

done