"expect" tests do not work on macos

[hannesm]

the underlying issue is that the default target on macos is macos, not unix. I've no clue how/whether expect based tests should cope with that -- maybe we should explicitly pass a target? or remove these tests? any suggestion? only observed in the opam-repository CI which includes executing tests on macos.

#=== ERROR while compiling mirage.4.2.0 =======================================#
# context              2.1.2 | macos/x86_64 | ocaml.4.14.0 | pinned(https://github.com/mirage/mirage/releases/download/v4.2.0/mirage-4.2.0.tbz)
# path                 ~/.opam/default/.opam-switch/build/mirage.4.2.0
# command              ~/.opam/opam-init/hooks/sandbox.sh build dune runtest -p mirage -j 11
# exit-code            1
# env-file             ~/.opam/log/mirage-67543-6504b4.env
# output-file          ~/.opam/log/mirage-67543-6504b4.out
### output ###
# (cd _build/default/test/mirage && ./test.exe)
# Testing `mirage'.
# This run has ID `27538NG6'.
# 
#   [OK]          basic          0   pp.
# 
# Full test results in `~/.opam/default/.opam-switch/build/mirage.4.2.0/_build/default/test/mirage/_build/_tests/mirage'.
# Test Successful in 0.000s. 1 test run.
# File "test/mirage/query/run.t", line 1, characters 0-0:
# /usr/bin/git --no-pager diff --no-index --color=always -u _build/.sandbox/15c2ed09e9f0f4404677e4f674252a1d/default/test/mirage/query/run.t _build/.sandbox/15c2ed09e9f0f4404677e4f674252a1d/default/test/mirage/query/run.t.corrected
# diff --git a/_build/.sandbox/15c2ed09e9f0f4404677e4f674252a1d/default/test/mirage/query/run.t b/_build/.sandbox/15c2ed09e9f0f4404677e4f674252a1d/default/test/mirage/query/run.t.corrected
# index 68f685f..6d06585 100644
# --- a/_build/.sandbox/15c2ed09e9f0f4404677e4f674252a1d/default/test/mirage/query/run.t
# +++ b/_build/.sandbox/15c2ed09e9f0f4404677e4f674252a1d/default/test/mirage/query/run.t.corrected
# @@ -36,7 +36,7 @@ Query opam file
#      "opam-monorepo" { build & >= "0.3.2" }
#    ]
#    
# -  x-mirage-opam-lock-location: "mirage/noop-unix.opam.locked"
# +  x-mirage-opam-lock-location: "mirage/noop-macosx.opam.locked"
#    
#    x-mirage-configure: ["sh" "-exc" "mirage configure --no-extra-repo"]
#    

[hannesm]

this has been fixed by #1425