[imgbb] Fix user extraction, add displayname

[Hrxn]

Just noticed this while extracting some albums.

Seems to fix it, of course, feel free to make any changes / adjustments etc.

[Hrxn]

displayname as in Displayed User Name, or "Full" User Name, whatever one wants to call it.

Change it if you're not happy with the name. I've picked it in analogy to displayName in behance.py, which works the same way, basically.

I've made tests with single links, couple of albums and a user. Seems working fine so far.
Well, user extraction is still running, should've taken a smaller example.

[Hrxn]

I've also checked it with a linter (https://github.com/astral-sh/ruff), might as well start doing it the right way when starting at all.

Aaaaand spoke too soon.
Of course.

ImgbbUserExtractor did extract all of the images listed on the profile page, but it apparently does not terminate.
It's still running, continually skipping downloads it already made. Seems like an infinite loop. Yeah, pretty sure, no need to wait here any longer, I think.

Well, I did not touch any pagination function or something, so, it's probably not my fault.. 😄

[mikf]

I've made tests with single links, couple of albums and a user. Seems working fine so far.

It doesn't work for albums without user info when logged in. (https://ibb.co/album/s9SKDs)
In this case, it extracts the name of the logged in user.

Don't worry about, though. I'll fix this myself before the next release.

Well, I did not touch any pagination function or something, so, it's probably not my fault.. 😄

The last real update to the imgbb code was in 2020 (9219141).
Not surprising that something broke during this time.

Fixed in 95c280c