Say I want something like this:

  1. Sequential: stage "build", build-type agent.

  2. Sequential: stage "tests" (this is just a wrapper/container)

    2.1 Parallel: stage "integration tests #1", integration #1-type agent

    2.2 Parallel: stage "integration tests #2, integration #2-type agent

    2.3 Parallel: stage "deploy and functional tests" (this is just a wrapper/container)

       2.3.1 Sequential: stage "deploy", deploy-type agent

       2.3.2 Sequential: stage "functional tests", functional-type agent