Sometimes, a healthcheck related test fails as occurred in
https://github.com/PostgREST/postgrest/actions/runs/19771357953/job/56655949002.
This happens due to freeport function accidently picking up a used port.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
(cherry picked from commit 50eec773bf)