With podman machine, gvproxy forwards published ports by binding them on
the host (not inside the VM) and runs unprivileged. macOS refuses to bind
a privileged port (< 1024) to a specific IP for a normal user, even though
binding all interfaces is fine, so publishing e.g. -p 127.0.0.1:80:80 used
to fail with an opaque "something went wrong with the request".
Pass the published ip:port into the gvproxy error helper and, when the body
says "permission denied" for a < 1024 port on a specific IP, return an
error that explains gvproxy binds on the host and suggests dropping the
host IP or using a port >= 1024. The raw body is kept for every other case.
Add unit tests for the helper.
Fixes: #28009
Signed-off-by: Grzegorz Szczepanczyk <g.szczepanczyk@getprintbox.com>
