meson: treat all fuzz cases as unit tests

meson: treat all fuzz cases as unit tests

318/365 fuzz-bus-message:crash-26bba7182dedc8848939931d9fcefcb7922f2e56:address  OK       0.03 s
319/365 fuzz-bus-message:crash-29ed3c202e0ffade3cad42c8bbeb6cc68a21eb8e:address  OK       0.03 s
320/365 fuzz-bus-message:crash-b88ad9ecf4aacf4a0caca5b5543953265367f084:address  OK       0.03 s
321/365 fuzz-bus-message:crash-c1b37b4729b42c0c05b23cba4eed5d8102498a1e:address  OK       0.03 s
322/365 fuzz-bus-message:crash-d8f3941c74219b4c03532c9b244d5ea539c61af5:address  OK       0.03 s
323/365 fuzz-bus-message:crash-e1b811da5ca494e494b77c6bd8e1c2f2989425c5:address  OK       0.03 s
324/365 fuzz-bus-message:leak-c09c0e2256d43bc5e2d02748c8d8760e7bc25d20:address  OK       0.04 s
325/365 fuzz-bus-message:message1:address       OK       0.03 s
326/365 fuzz-bus-message:timeout-08ee8f6446a4064db064e8e0b3d220147f7d0b5b:address  OK       0.03 s
327/365 fuzz-dhcp-server:discover-existing:address  OK       0.04 s
328/365 fuzz-dhcp-server:discover-new:address   OK       0.03 s
329/365 fuzz-dhcp-server:release:address        OK       0.04 s
330/365 fuzz-dhcp-server:request-existing:address  OK       0.03 s
331/365 fuzz-dhcp-server:request-new:address    OK       0.03 s
332/365 fuzz-dhcp-server:request-reboot:address  OK       0.03 s
333/365 fuzz-dhcp-server:request-renew:address  OK       0.03 s
334/365 fuzz-dns-packet:issue-7888:address      OK       0.03 s
335/365 fuzz-dns-packet:oss-fuzz-5465:address   OK       0.03 s
336/365 fuzz-journal-remote:crash-5a8f03d4c3a46fcded39527084f437e8e4b54b76:address  OK       0.06 s
337/365 fuzz-journal-remote:crash-96dee870ea66d03e89ac321eee28ea63a9b9aa45:address  OK       0.04 s
338/365 fuzz-journal-remote:invalid-ts.txt:address  OK       0.04 s
339/365 fuzz-journal-remote:oss-fuzz-8659:address  OK       0.06 s
340/365 fuzz-journal-remote:oss-fuzz-8686:address  OK       0.04 s
341/365 fuzz-journal-remote:sample.txt:address  OK       0.07 s
342/365 fuzz-unit-file:directives.service:address  OK       0.03 s
343/365 fuzz-unit-file:empty.scope:address      OK       0.04 s
344/365 fuzz-unit-file:machine.slice:address    OK       0.03 s
345/365 fuzz-unit-file:oss-fuzz-6884:address    OK       0.05 s
346/365 fuzz-unit-file:oss-fuzz-6885:address    OK       0.03 s
347/365 fuzz-unit-file:oss-fuzz-6886:address    OK       0.04 s
348/365 fuzz-unit-file:oss-fuzz-6892:address    OK       0.03 s
349/365 fuzz-unit-file:oss-fuzz-6897:address    OK       0.05 s
350/365 fuzz-unit-file:oss-fuzz-6897-evverx:address  OK       0.04 s
351/365 fuzz-unit-file:oss-fuzz-6908:address    OK       0.05 s
352/365 fuzz-unit-file:oss-fuzz-6917:address    OK       0.06 s
353/365 fuzz-unit-file:oss-fuzz-6977:address    OK       0.08 s
354/365 fuzz-unit-file:oss-fuzz-6977-unminimized:address  OK       0.10 s
355/365 fuzz-unit-file:oss-fuzz-7004:address    OK       0.03 s
356/365 fuzz-unit-file:oss-fuzz-8064:address    OK       0.03 s
357/365 fuzz-unit-file:oss-fuzz-8827:address    OK       0.50 s
358/365 fuzz-unit-file:proc-sys-fs-binfmt_misc.automount:address  OK       0.03 s
359/365 fuzz-unit-file:syslog.socket:address    OK       0.03 s
360/365 fuzz-unit-file:systemd-ask-password-console.path:address  OK       0.03 s
361/365 fuzz-unit-file:systemd-machined.service:address  OK       0.03 s
362/365 fuzz-unit-file:systemd-resolved.service:address  OK       0.03 s
363/365 fuzz-unit-file:systemd-tmpfiles-clean.timer:address  OK       0.03 s
364/365 fuzz-unit-file:timers.target:address    OK       0.03 s
365/365 fuzz-unit-file:var-lib-machines.mount:address  OK       0.04 s

This gives us slightly nicer coverage in the normal test run.

When in a git repo, git ls-files is used to get a list of files known to git.
This mirrors what update-man-rules does for man files. Only looking at files
known to git makes it easier to not forget to commit the test file to git,
and also makes bisecting easier if some files are left in repo.

When outside of a git repo, we expect to be unpacked from a tarball, so just
using all files reported by ls is OK.