utils: Rewrite run-tests.sh to use functions and extenal scripts

To modify Azure tests and depend on shell scripts and pytest instead
of molecule, the run-tests.sh script has been rewritten to depend on
bash functions and on a bash script that prepare and start a testing
container.

This patch adds a new script, 'utils/setup_test_container.sh' that
can be used to start a new container, using either podman or docker,
based on the available ansible-freeipa images. The new container can
then be used to run ansible-freeipa tests against it.

Also the following files with bash functions were added, and are
used by both scripts:

    utils/shansible: Functions to run playbooks in the container
    utils/shcontainer: Functions to setup/run a container
    utils/shfun: Generic shell helper functions (e.g.: log)