Make it possible to perform actions before and after experiments

Before and after experiments, it may be necessary to perform actions, such as resetting Kafka Topics.

To enable this, the existing benchmark structure should be extended as follows:

...
infrastructure:
  # Action before and after exections
  beforeExecution:
    resources:
       - list of K8s resources which are deployed before an execution is started
    commands:
       - Commands called on existing pods
  afterExecution: 
    resources:
      - list of K8s resources which are deployed after an execution is executed
    commands:
       - Commands called on existing pods
  # Action before and after individual slo experiments
  beforeExperiment:
    resources:
       - list of K8s resources which are deployed before an experiment is started
    commands:
       - Commands called on existing pods
  afterExperiment: 
...
    resources:
      - list of K8s resources which are deployed after an experiment is executed
    commands:
       - Commands called on existing pods