[Development] @Maintainers: please update "What's New in Qt 6.10"

[Vladimir Minenko]

Hi all,

I might be already almost famous for those reminders :-)

@Maintainers: 

I recently went to

https://doc-snapshots.qt.io/qt6-6.10/whatsnew610.html

and I saw many sections we are empty at all or have suspiciously short content.

We have beta2 for 6.10 now. Actually, the scope schould be frozen enough by now so that this page would have a known content.

Can you please make sure that this page is updated?

If a section did have any addtions worthnotting, please remove this section so that it does not look forgotten.

Thanks!

--
Vladimir