Disable GC even during finalizing

We're seeing a crash during shutdown in rb_gc_impl_objspace_free because
it's running lazy sweeping during shutdown. It appears that it's due to
`finalizing` being set, which causes GC to not be aborted and not
disabled which causes it to be in lazy sweeping at shutdown.

The full stack trace is:

    #6  rb_bug (fmt=fmt@entry=0x5643b8ebde78 "lazy sweeping underway when freeing object space") at error.c:1095
    #7  0x00005643b8a3c697 in rb_gc_impl_objspace_free (objspace_ptr=<optimized out>) at gc/default.c:9507
    #8  0x00005643b8c269eb in ruby_vm_destruct (vm=0x7e2fdc84d000) at vm.c:3141
    #9  0x00005643b8a5147b in rb_ec_cleanup (ec=<optimized out>, ex=<optimized out>) at eval.c:263
    #10 0x00005643b8a51c93 in ruby_run_node (n=<optimized out>) at eval.c:319
    #11 0x00005643b8a4c7c7 in rb_main (argv=0x7fffef15e7f8, argc=18) at ./main.c:43
    #12 main (argc=<optimized out>, argv=<optimized out>) at ./main.c:62

0 files changed, 0 insertions, 0 deletions