refactor fronting-proxy-port tests
refactor fronting-proxy-port tests

`ssl-redirect` configuration is going to be moved to the backend and
such functionality impacts `fronting-proxy-port`. This refactor moves
two fronting proxy tests inside a single one and reuses some
configuration snippet. This will make easier to evolve the tests.

jcmoraisjr/haproxy-ingress,jcmoraisjr/haproxy-ingress