Add ubuntu 20.04 to CI as it has podman 2.0.1 version (#83)

Fix idempotency issues in podman_container
Add creating workdir, buildah issue: https://github.com/containers/buildah/issues/2475
Fix #68
Fix #69
Should help to #80 as well, but will be handled separately.

ci/run_connection_test.sh

@@ -39,4 +39,4 @@ if [[ "$CON_TYPE" == "podman" ]]; then
 elif [[ "$CON_TYPE" == "buildah" ]]; then
     ${SUDO} buildah rm buildah-container
 fi
-${SUDO} rm -f /tmp/local_file
+sudo rm -f /tmp/local_file /tmp/remote_file

ci/run_containers_tests.sh

@@ -15,7 +15,8 @@ exit_code=0
 CMD="ANSIBLE_ROLES_PATH=${CURWD}/../tests/integration/targets \
     ${ANSIBLECMD:-ansible-playbook} \
     -i localhost, -c local --diff \
-    ci/playbooks/containers/${TEST2RUN}.yml"
+    ci/playbooks/containers/${TEST2RUN}.yml \
+    -e ansible_python_interpreter=$(command -v python)"
 
 bash -c "$CMD -vv" || exit_code=$?
 if [[ "$exit_code" != 0 ]]; then