Remove Qt Single Application support
Hey!
I believe we can remove Qt Single Application support for the following reasons:
- The default value for
KDEVELOP_SINGLE_APP
is false thus you have to enable it if you want Single App enabled KDevelop. - It will easen the Qt6 port by not having this to test and port.
- There hasnt been "real" activity to it for 5 years in this repository and same with the main one.
Signed-off-by: António Monteiro antonio.fmr.monteiro@gmail.com