Add podman compatibility to Makefile

[Elyytscha]

I would like to use podman for building the argocd operator instead of docker, without breaking it for people who still use docker.

Is your feature request related to a problem? Please describe.
I'm using Fedora and the Podman Buildah stack, so i have no Docker installed, so per default i can't build the operator

Describe the solution you'd like
Makefile could detect if it can use docker or podman