* move `id: can-reproduce` to first position to give incentivize reproducers.
If the description comes first, the person filing the bug report
will describe the problem in plain English. It is better if the
first thing they do, if at all possible, is to create a reproducer
and provide a link.
* remove `id: os-ver` as it has never been relevant.
* do not require `id: forgejo-ver` because it does not matter that much
as long as it can be reproduced on try.next.
* remove "If the error appears to relate to Forgejo the server" as it
has never been relevant.
* require the description
* move `id: can-reproduce` to first position to give incentivize reproducers.
If the description comes first, the person filing the bug report
will describe the problem in plain English. It is better if the
first thing they do, if at all possible, is to create a reproducer
and provide a link.
* remove `id: screenshots` as they can be copy/pasted to the
description when relevant. They are more important int the UI
bug report template but not so much here.
* remove `id: git-ver` as it is almost never relevant. If it is, this
can be included in the description but clutters the template most of
the time.
* remove `id: os-ver` as it is redundant with what `id: run-info`
requires.
* dev.next.forgejo.org is running the latest development branch
* link to dev.next.forgejo.org instead of next.forgejo.org