Automate the update of the cilium version in tests

[matheuscscp]

The version is hardcoded in the makefile. In order to automatically update we need a periodic GitHub Actions that spins up a kind cluster, installs FluxCD using the setup action from controlplaneio-fluxcd/distribution/actions/setup, creates a Flux ImageRepository and ImagePolicy with the flux CLI to find the latest cilium image in the semver range 1.x, then creates a Flux GitRepository with the temporary GITHUB_TOKEN of the action and a Flux ImageUpdateAutomation with this GitRepository to update the cilium image inside a YAML file in the repo. This file needs to be created and the makefile needs to read the cilium version from it when needed.