git-unix.3.0.0: disable tests
git-unix.3.0.0: disable tests

They always fail with the following.
```
 Testing `smart'.
 This run has ID `626A8108-A062-4202-AD53-B3A5585B32DE'.

   [OK]          regression          0   empty clone.
   [OK]          regression          1   simple clone.
   [OK]          regression          2   simple push.
   [OK]          regression          3   push error.
   [OK]          regression          4   fetch empty.
 > [FAIL]        regression          5   negotiation.
   [FAIL]        regression          6   clone over ssh.
   [FAIL]        regression          7   fetch over ssh.
   [FAIL]        regression          8   push over ssh.
   [FAIL]        regression          9   fetch over http.
   [FAIL]        regression         10   partial clone over ssh.
   [OK]          regression         11   partial fetch.
   [OK]          regression         12   Sync.fetch fetches given remote ref a...

 ┌──────────────────────────────────────────────────────────────────────────────┐
 │ [FAIL]        regression          5   negotiation.                           │
 └──────────────────────────────────────────────────────────────────────────────┘
 [EXEC:5660][bos]: ['git' 'init']
 Initialized empty Git repository in /tmp/buildd70025.dune/git-dd6819/.git/
 ASSERT link pack-testzone-0.pack to /tmp/buildd70025.dune/git-dd6819/.git/objects/pack/pack-4aae6e55c118eb1ab3d1e2cd5a7e4857faa23d4e.pack: Invalid cross-device link
 FAIL link pack-testzone-0.pack to /tmp/buildd70025.dune/git-dd6819/.git/objects/pack/pack-4aae6e55c118eb1ab3d1e2cd5a7e4857faa23d4e.pack: Invalid cross-device link
 Raised at Alcotest_engine__Test.check_err in file "src/alcotest-engine/test.ml", line 158, characters 20-48
 Called from Alcotest_lwt.run_test.(fun) in file "src/alcotest-lwt/alcotest_lwt.ml", line 29, characters 47-57
 Called from Lwt.Sequential_composition.try_bind in file "src/core/lwt.ml", line 2133, characters 16-20

 Logs saved to `~/.opam/4.12/.opam-switch/build/git-unix.3.0.0/_build/default/test/smart/_build/_tests/smart/regression.005.output'.
  ──────────────────────────────────────────────────────────────────────────────

 Full test results in `~/.opam/4.12/.opam-switch/build/git-unix.3.0.0/_build/default/test/smart/_build/_tests/smart'.
 6 failures! in 0.258s. 13 tests run.
```

Signed-off-by: Marcello Seri <34fd14c67154e888f6587d5c0e7eadd13aaf7ca7@gmail.com>

pqwy/opam-repository,mjambon/opam-repository,astrada/opam-repository,emillon/opam-repository,codinuum/opam-repository,jonludlam/opam-repository,andersfugmann/opam-repository,toots/opam-repository,fpottier/opam-repository,Chris00/opam-repository,toots/opam-repository,jonludlam/opam-repository,c-cube/opam-repository,djs55/opam-repository,hannesm/opam-repository,lefessan/opam-repository,kkirstein/opam-repository,Chris00/opam-repository,jhwoodyatt/opam-repository,pirbo/opam-repository,pqwy/opam-repository,nberth/opam-repository,astrada/opam-repository,ocaml/opam-repository,codinuum/opam-repository,pirbo/opam-repository,yallop/opam-repository,jhwoodyatt/opam-repository,andersfugmann/opam-repository,kkirstein/opam-repository,yallop/opam-repository,hannesm/opam-repository,lefessan/opam-repository,seliopou/opam-repository,ocaml/opam-repository,abate/opam-repository,fpottier/opam-repository,seliopou/opam-repository,emillon/opam-repository,c-cube/opam-repository,Leonidas-from-XIV/opam-repository,djs55/opam-repository,Leonidas-from-XIV/opam-repository,nberth/opam-repository,mjambon/opam-repository