Don't really know a better name for this. I've gone through some Forms
and added missing HTML attributes (mostly `maxlength`). I tried to fill
the Forms with dummy Data and see if Gitea throws a Error (e.g. maximum
length). If yes, I added the missing HTML attribute.
While working on this, I discovered that the Form to add OAuth2 Apps
just silently fails when filled with invalid data, so I fixed that too.
85fa954a38