Add switch to skip fetching certificates auto{config,discover} subdomains

[schichtnudelauflauf]

Add switch to skip fetching certs for auto{config,discover} subdomains.

Might be useful in certain reverse proxy situations.

This is a cleaned up version of #5474

The things discussed there are changed and I made a better name.
I had to open a new PR due to Github Web UI limitations.

The old PR that is linked can bre closed.

@jennypaxian, pinging you too because you'll not be auto notified.

[schichtnudelauflauf]

(Offtopic: How much I hate that the webinterface does sign my commits with a key I don't control. I'd rather they were unsigned. Sheesh.)

[dragoangel]

You feel that variable definitely is too long?

AUTODISCOVER_SAN=y/n and should be y by default in compose when unset. Don't want autodiscover, put it to n

[schichtnudelauflauf]

that sounds kinda ambiguous but I'll put it if it gets it merged 😁

[jennypaxian]

You feel that variable definitely is too long?

AUTODISCOVER_SAN=y/n and should be y by default in compose when unset. Don't want autodiscover, put it to n

Sounds good to me, also thanks y'all for following up on it.

[schichtnudelauflauf]

Ok now after snail fast editing of things on my phone the name is changed, default flipped.

[dragoangel]

Well now it looks cleaner for me, thanks.

[schichtnudelauflauf]

Just in case, I couldn't squash the commits together with the webinterface from the phone. I have no laptop nearby. But you'll merge squashed anyways ig?

[schichtnudelauflauf]

Can I get a yes or no here?