feat: add AlmaLinux and Rocky Linux support

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

build(deps): bump github.com/docker/distribution

Bumps [github.com/docker/distribution](https://github.com/docker/distribution) from 2.8.1+incompatible to 2.8.2+incompatible.
- [Release notes](https://github.com/docker/distribution/releases)
- [Commits](distribution/distribution@v2.8.1...v2.8.2)

---
updated-dependencies:
- dependency-name: github.com/docker/distribution
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>

actions: move ubuntu 18 runners to latest

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

deps: go mod tidy

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

docs: document dependencies and docker install method (close #10)

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

actions: run tests only if go files or templates changed

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

run/hetzner: rollback sparsecat using outside linux

Makefile: compute tag: ignore dirty state

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

goreleaser: do not run go generate

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

sysconfig: fix paths for ubuntu versions before 20.04 (fix #3)

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

d2vm: fix CentOS install

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>