Summary
For running IT tests of `kn-plugin-workflow`, you need to have installed:

• docker
• podman

Those are currently not mentioned in README and should be, because they are needed to run `pnpm -r build:prod` if `KIE_TOOLS_BUILD__runIntegrationTests` is set to `true`.

Acceptance criteria
README is updated and has prerequisites of docker and podman in appropriate versions added.