fix(bootstrap-os): do not install pkgs requirements on flatcar (#11252)

Fix regression added in 663fcd10 for
flatcar nodes.

See: https://github.com/kubernetes-sigs/kubespray/commit/663fcd104c38ddc2bf8c023f6f6b3705048d531e



Co-authored-by: Anthony Delannoy <adelannoy@wiremind.io>