Enable caching for integration tests

[jonastheis]

If we enable caching via any of these options we should be able to speed up at least the pulling of dependencies and building by a large margin.

This already takes a little bit longer than 3min.

[georgysavva]

It seems that the article that you mentioned is a bit old.
Here are the official docket GH actions to achieve image layers caching via Github caching:
https://github.com/docker/build-push-action/blob/master/docs/advanced/cache.md
And complete third-party article as a bonus:
https://evilmartians.com/chronicles/build-images-on-github-actions-with-docker-layer-caching
I will try to pull this off.

[georgysavva]

@capossele Why did we close this issue?

[capossele]

My bad, I thought we were done with this. I'll reopen it

[georgysavva]

After running several benchmarks it turned out that docker layer caching doesn't give any performance benefit due to the fact that we can not cache the Go build. So we should get back this when they fix that in moby/buildkit#1512
@jonastheis