Switch test environment to docker driver

The podman driver is flakeky locally and consistently failing in github
actions now. Switching to docker fix the issues in github.

Developers need to install docker to run drenv test locally. I tried to
use the podman-docker pacakge but it does not emulate docker good
enough for minikube.

Signed-off-by: Nir Soffer <nsoffer@redhat.com>

test/README.md

@@ -37,21 +37,30 @@ environment.
    [Install clusteradm CLI tool](https://open-cluster-management.io/getting-started/installation/start-the-control-plane/#install-clusteradm-cli-tool)
    for the details. Version 0.5.0 or later is required.
 
-1. Install `podman`
+1. Install `docker`
 
    ```
-   sudo dnf install podman
+   sudo dnf install docker
    ```
 
-   Allow yourself to run podman as root without a password by adding
-   this file as root:
+   Add yourself to the `docker` group to allow running docker as root:
 
    ```
-   # cat /etc/sudoers.d/podman
-   # Allow passwordless podman
-   myusername ALL=(ALL) NOPASSWD: /usr/bin/podman
+   sudo usermod -aG docker $USER && newgrp docker
    ```
 
+   Restart docker service to fix the permissions on the docker daemon
+   socket:
+
+   ```
+   sudo systemctl restart docker
+   ```
+
+   For more info see [Linux post-installation steps for Docker Engine](https://docs.docker.com/engine/install/linux-postinstall/).
+
+   docker is used only for running drenv tests locally. You can use
+   podman for building and running containers locally.
+
 ### Testing that drenv is healthy
 
 Run this script to make sure `drenv` works:

test/envs/test.yaml

@@ -6,8 +6,7 @@
 name: test
 profiles:
   - name: cluster
-    driver: podman
-    container_runtime: cri-o
+    driver: docker
     memory: 2g
     workers:
       - addons: