Add e2e tests

[kvaps]

List of tests we run manually

phase1:

• Create three VMs with Talos
• Deploy Kubernetes on them
• Apply cozystack.yaml
• kubectl get hr -A - should return all okay within 5 minutes

phase2:

• Deploy monitoring, etcd, ingress
• Deploy one instance of each from packages/apps
• kubectl get hr -A - should return all okay within 5 minutes
• tests for updates

[nbykov0]

Steps:

1. privision nodes
2. non-interactively install Cozystack
3. run tests, output results

1 -- a script which would support running a set of VMs on a set of "backends": kvm, virtualbox, aws, etc. Vagrant looked nice but was considered dead
2 -- talm should help
3 -- sonobuoy looks nice as a test execution engine, however a list of tests is still a wip

[nbykov0]

See also:
#94
#98