Lin Out_channel test fails to trigger on FreeBSD

[jmid]

The Lin Out_channel test may fail to trigger on FreeBSD:
https://ocaml-multicoretests.ci.dev:8100/job/2023-10-09/211619-ci-ocluster-build-4fc644

random seed: 189380608
generated error fail pass / total     time test name

[ ]    0    0    0    0 / 1000     0.0s Lin DSL In_channel test with Domain
[ ]    0    0    0    0 / 1000     0.0s Lin DSL In_channel test with Domain (generating)
[✓]   78    0    1   77 / 1000     6.2s Lin DSL In_channel test with Domain

[ ]    0    0    0    0 / 5000     0.0s Lin DSL Out_channel test with Domain
[ ]  138    0    0  138 / 5000    54.2s Lin DSL Out_channel test with Domain
[ ]  237    0    0  237 / 5000   126.7s Lin DSL Out_channel test with Domain
[ ]  392    0    0  392 / 5000   210.4s Lin DSL Out_channel test with Domain
[ ]  539    0    0  539 / 5000   270.7s Lin DSL Out_channel test with Domain
[ ]  604    0    0  604 / 5000   365.7s Lin DSL Out_channel test with Domain
[ ]  658    0    0  658 / 5000  1433.8s Lin DSL Out_channel test with Domain
[ ]  785    0    0  785 / 5000  1498.0s Lin DSL Out_channel test with Domain
[ ] 1097    0    0 1097 / 5000  1576.1s Lin DSL Out_channel test with Domain
[ ] 1211    0    0 1211 / 5000  1640.9s Lin DSL Out_channel test with Domain
[ ] 1479    0    0 1479 / 5000  1767.2s Lin DSL Out_channel test with Domain
[ ] 1624    0    0 1624 / 5000  2064.6s Lin DSL Out_channel test with Domain
[ ] 1637    0    0 1637 / 5000  2345.4s Lin DSL Out_channel test with Domain
[ ] 1743    0    0 1743 / 5000  2422.5s Lin DSL Out_channel test with Domain
[ ] 1753    0    0 1753 / 5000  2488.0s Lin DSL Out_channel test with Domain
[ ] 1898    0    0 1898 / 5000  3714.9s Lin DSL Out_channel test with Domain
[ ] 2262    0    0 2262 / 5000  3776.0s Lin DSL Out_channel test with Domain
[ ] 2400    0    0 2400 / 5000  3836.1s Lin DSL Out_channel test with Domain
[ ] 2550    0    0 2550 / 5000  3921.0s Lin DSL Out_channel test with Domain
[ ] 2893    0    0 2893 / 5000  3984.7s Lin DSL Out_channel test with Domain
[ ] 2933    0    0 2933 / 5000  4658.3s Lin DSL Out_channel test with Domain
[ ] 3020    0    0 3020 / 5000  4864.7s Lin DSL Out_channel test with Domain
[ ] 3165    0    0 3165 / 5000  4989.6s Lin DSL Out_channel test with Domain
[ ] 3420    0    0 3420 / 5000  5102.8s Lin DSL Out_channel test with Domain
[ ] 3511    0    0 3511 / 5000  5419.8s Lin DSL Out_channel test with Domain
[ ] 3703    0    0 3703 / 5000  5488.8s Lin DSL Out_channel test with Domain
[ ] 3943    0    0 3943 / 5000  5551.9s Lin DSL Out_channel test with Domain
[ ] 4050    0    0 4050 / 5000  5725.2s Lin DSL Out_channel test with Domain
[ ] 4352    0    0 4352 / 5000  5788.9s Lin DSL Out_channel test with Domain
[ ] 4397    0    0 4397 / 5000  5977.5s Lin DSL Out_channel test with Domain
[ ] 4566    0    0 4566 / 5000  8545.2s Lin DSL Out_channel test with Domain
[ ] 4702    0    0 4702 / 5000  8606.3s Lin DSL Out_channel test with Domain
[✗] 5000    0    0 5000 / 5000  8654.9s Lin DSL Out_channel test with Domain