test: fixed use of `client.host` in legacy test: those tests are not maintained anymore, but as the use of `client.host` as been fixed elsewhere, it was the occasion to do it there too. Those legacy tests should be ported or to the new workflow, or deleted if they are not relevant anymore.

version: "3.6"
services:

  sat:
    image: salutatoi/sat
    build: backend

  libervia:
    build: libervia
    depends_on:
      - sat