To free up build in Travis, we decided to run the non-flaky parts of
the CI pipeline in GitHub Workflows/Actions only. The integration tests
on the other hand are removed from GitHub because individual actions
cannot be restarted there which caused us to restart the whole workflow
if one test was flaky.
This split should give us the best of both worlds: Fast run of small
checks, linting and unit tests with an easy overview of what failed in
the PR directly. And more free build slots on Travis to do more advanced
integration tests on other architectures and/or operating systems. And
the option to restart a single flaky integration test on Travis.
Checkout v1 has a known flake:
https://github.com/actions/checkout/issues/23#issuecomment-572688577.
For our linter to pass, we need to checkout our full history (default
depth is 1 commit). We could set fetch-depth, but we will eventually
move that depth past the linter's start point commit and need to
implement another fix. Indead, we add an extra step in our linter to
fetch full history so that the linter reference commit is found.
The continue-on-error was added to make sure the log files of the
failed itests would always be uploaded. But this has the side effect
of marking the whole job successful, even if the itest job itself
failed. The failure condition in the log file steps already solve
that, so the continue-on-error is not needed anymore.