Add instructions on using Podman

make test will work just fine in Podman, provided the Docker-compatible
socket is set up and the `DOCKER_HOST` environment variable is set. This
allows the Docker API client libraries used by ory/dockertest to
provision Podman containers.

Signed-off-by: Alexander Scheel <alex.scheel@control-plane.io>

Author: cipherboy

DEVELOPMENT.md

@@ -10,9 +10,18 @@ There are a number of dependencies required to be able to run the controller and
 
 - [Install Go](https://golang.org/doc/install)
 - [Install Kustomize](https://kubernetes-sigs.github.io/kustomize/installation/)
-- [Install Docker](https://docs.docker.com/engine/install/)
+- [Install Docker](https://docs.docker.com/engine/install/) or [Podman](https://podman.io/).
 - (Optional) [Install Kubebuilder](https://book.kubebuilder.io/quick-start.html#installation)
 
+> [!NOTE]
+>
+> When using Podman, start the user daemon before running the tests:
+>
+> ```shell
+> systemctl --user enable --now podman.socket
+> export DOCKER_HOST=unix:///run/user/1000/podman/podman.sock
+> ```
+
 ## How to run the test suite
 
 Prerequisites:
@@ -24,6 +33,9 @@ You can run the test suite by simply doing
 make test
 ```
 
+These tests spin up containers using `ory/dockertest` and will read
+`DOCKER_HOST`.
+
 ## How to run the controller locally
 
 Install the controller's CRDs on your test cluster:
@@ -91,4 +103,4 @@ Deploy `kustomize-controller` into the cluster that is configured in the local k
 make deploy
 ```
 
-Running the above will also deploy `source-controller` and its CRDs to the cluster.
+Running the above will also deploy `source-controller` and its CRDs to the cluster.