Allow creation and storing of superruns if SaveWhen > 0

[WenzDaniel]

What is the problem / what does the code in this PR do
Changed get_components such that superruns can be created from every plugin type except SaveWhen.NEVER plugins. This addresses: XENONnT/straxen#605

[JoranAngevaare]

Quick question, although this seems to works, would it not be more intuitive to always make the data when making a super-run, also when using a SaveWhen.NEVER plugin or do you foresee a reason why not to do this? Otherwise, for SaveWhen.NEVER we will keep the same behavior right?

[WenzDaniel]

Yes, I thought about it too. But in the end I decided against it to distinguish more explicitly between SaveWhen.NEVER and SaveWhen.EXPLICIT. I think the latter was added later, was not it? At least I had the impression that SaveWhen.EXPLICIT makes SaveWhen.NEVER a bit obsolete. I think any plugin should be saveable if asked for, unless there might be some technical reasons for which we would forbid saving and make it a SaveWhen.NEVER plugin.

But one thing which just comes to my mind. Since a superrun cannot be created in that case I should raise an error early.

[JoranAngevaare]

Right, I never used savewhen explicit, I had to write a test to understand it:
#510

But agree, SaveWhen.Never is a bit of a strange choice generally when SaveWhen.Explicit is available