feat: look for and use existing podman installation as well as Docker

[g0ddest]

Motivation

As said in #3949 jib works with hardcoded docker executable name. But there are alternative software (podman, rancher, ...) and it's good to provide out-of-box for the most popular ones.

Implementation

I made from DEFAULT_DOCKER_CLIENT as list of the most popular container software (docker and podman in this PR).

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