Dropping Qt5 CI Support at the End of September 2025

[Albert Astals Cid]

Hi everyone, 

While this has been discussed in various forums, it has not yet been the main 
focus of any conversation.

We are planning to drop support for Qt5 CI on invent.kde.org at the end of 
September 2025.

If you are still using Qt5 you have 3 months to move to Qt6 or you can try to 
convince the powers that you need more time with a really good reason.

Cheers,
  Albert