Create new workflow hooks, PRE and POST experiment

[oyvindeide]

Is your feature request related to a problem? Please describe. There are some workflows that it would be good to run before the run model starts, and some workflows that might clean up after everything is done.

Describe the solution you'd like Add a new hook before and after this step: https://github.com/equinor/ert/blob/4496033be04dab7622780034a19d7ace9902a514/src/ert/run_models/base_run_model.py#L257

I dont think these hooks should have access to storage and any ensembles, as they run outside that context, but that is up for discussion.

We might want the option to add more hooks after we create the experiment, but no ensembles exists, so need to think about the naming.

[dafeda]

Could you give some concrete examples of workflows that it would be useful to run pre and post experiment?

[oyvindeide]

There are some current users that run a few manual workflows before they start an experiment today, examples could be setting up authentication, creating some shared folders, etc. After an experiment, some users would like to run some cleanup workflows and aggregation workflows.

[sondreso]

See also: https://github.com/equinor/ert/issues/8987