Resolve Java 21 FTBFS
This MR resolves: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1053024
There are changes in compiler type inference that caused compile errors. They were resolved upstream in https://github.com/eclipse/eclipse-collections/tree/master. I have cherry-picked them into a patch.
Alternative is to package eclipse-collections and retire gs-collections package.
Testing:
- build in sid chroot with default Java 21
- build in sid chroot