[LyX/master] Fix AboutLyX layout

[Pavel Sanda]

On Mon, Nov 04, 2024 at 07:54:50AM +0100, Jürgen Spitzmüller wrote:
> Am Sonntag, dem 03.11.2024 um 20:03 +0100 schrieb Pavel Sanda:
> > I see this, but it seems to compile just fine on old system (Qt
> > 5.15.8).
> 
> Yes it does, but it does not work (neither on old nor on new systems)
> as it is invalid. Spacers using this, for instance, are simply ignored.

We could easily automatize check for this in our tests.

I can add it if you write some list of string we should
grep for in .ui files...

Pavel