…e ingress daemon

When the ingress spec is built a virtual_ip parameter is provided in the spec and it's
expected to see the haproxy instance using the defined value.
The defined VIP is properly configured using the keepalived instance and, as per doc [1],
the ingress should be able to use this value as entrypoint for the haproxy frontend.
This patch also introduces a basic unit test for the IngressService with the purpose of
validating the config files generated for both haproxy and keepalived.

[1] https://docs.ceph.com/en/latest/cephadm/services/rgw/#high-availability-service-for-rgw

Fixes: https://tracker.ceph.com/issues/53684
Signed-off-by: Francesco Pantano <fpantano@redhat.com>
(cherry picked from commit 0688ca9)
Signed-off-by: Sebastian Wagner <sewagner@redhat.com>

Conflicts:
	src/pybind/mgr/cephadm/tests/test_services.py

The current configuration of keepalived makes it do
a curl on localhost:9999 in order to check the endpoint is alive.
Given the endpoint only binds on the vip addr, that doesn't work.

Fixes: https://tracker.ceph.com/issues/53807

Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>