Migrate the CI jobs to using GitHub actions

[fidencio]

Currently our CI jobs are using a jenkins instance, where we have to maintain the jenkins instance, and also have to maintain a bunch of scripts related to the deployment that are not exactly related to Kata Containers.

When testing Kata Containers, we should be only caring about the Kata Containers binaries, rather than spending time / effort maintaining k8s deployments and configurations.

Azure, which we already use for each VM that's part of our CI, can be easily integrated with GitHub actions, and we should evaluate using it for each case that makes sense, and keep only the bare minimum jobs as part of our jenkins instance (none, in the best case scenario).