Fix description boxes smaller than 3 lines

[amogusussy]

If a video has no description, (without this commit) the description box will still take up 8.3em, even if there's no content in it.

This PR fixes that issue.

[amogusussy]

Example without this PR:
https://i.imgur.com/F7BoIfw.png

With this PR:
https://imgur.com/5j55WAG.png

[pklion]

I think it's caused by #3660 and it shouldn't be fixed with CSS, I suppose.

[SamantazFox]

I think it's caused by #3660 and it shouldn't be fixed with CSS, I suppose.

Yes, this is indeed caused by #3660
for the record, here is a video that has actually no description: https://test.invidious.io/watch?v=iuevw6218F0

However, this fix can still be relevant for videos with a one or two lines description!

[pklion]

However, this fix can still be relevant for videos with a one or two lines description!

I agree.

[SamantazFox]

Thanks for your contribution :)