source_file/2 causes test case to fail.

[EricGT]

On Ubuntu 22.04 LTS on WSL 2 on Windows 10 with SWI-Prolog 8.5.15

groot@Galaxy:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 22.04.1 LTS
Release:        22.04
Codename:       jammy

?- version.
Welcome to SWI-Prolog (threaded, 64 bits, version 8.5.15-86-g5a3743ab9)

---

?- pack_rebuild(ffi).

results in

% ERROR: /home/groot/.local/share/swi-prolog/pack/ffi/test/test_libc.pl:88:
%       test stat: failed

due to this line

once(source_file(_:stat(_,_), File)),

Changing to

once(source_file(File)),

results in success.