Verifying issues on Gitlab

[Federico Bruni]

Hi all

I've started verifying issues on Gitlab.
It's quite straightforward, but still boring :-)
I think that most of the times it's "useless", meaning that I can't 
find any error.. but sometimes you may find something useful to report: 
a new command to be documented, an unclear new feature, etc.

The problem is that the number of issues to be verified, only for 
2.21.0, is still huge (552):
https://gitlab.com/lilypond/lilypond/-/issues?scope=all&utf8=%E2%9C%93&state=closed&label_name[]=Fixed_2_21_0&label_name[]=Status%3A%3AFixed

and only 21 issues have been verified so far:
https://gitlab.com/lilypond/lilypond/-/issues?scope=all&utf8=%E2%9C%93&state=closed&label_name[]=Fixed_2_21_0&label_name[]=Status%3A%3AVerified

If nobody else jumps in, I will probably give up soon.