Python 3.14 changed the multiprocessing fork mode to "forkserver",
presumably for good reasons. However, it conflicts with our
relocatable Python system. "forkserver" forks and execs a Python
process at startup, but it does this without supplying our relocated
ld.so. The system ld.so detects a conflict and crashes.
Fix this by switching back to "fork", which is sufficient for
housekeeping's modest needs.
Closesscylladb/scylladb#26831
8e480110c2