Ingress/scheme

[PietroPasotti]

Based on #190

Fixes #188

In tandem with: canonical/alertmanager-k8s-operator#173

[sed-i]

Would you mind changing the merge target to #190 temporarily, so the diff is easier?

[sed-i]

@PietroPasotti, I made a few fixes in the itests but there is an issue with the refactored tcp reldata.

tests/integration/test_charm_tcp.py::test_relation_data_shape

AssertionError: assert {'tcp-tester/...cp-tester-0'}} == {'tcp-tester/....8.219:9999'}}
  Differing items:
  {'tcp-tester/0': {'url': 'http://10.43.8.219/test-charm-tcp-i4iy-tcp-tester-0'}} != {'tcp-tester/0': {'url': '10.43.8.219:9999'}}
  Full diff:
  - {'tcp-tester/0': {'url': '10.43.8.219:9999'}}
  + {'tcp-tester/0': {'url': 'http://10.43.8.219/test-charm-tcp-i4iy-tcp-tester-0'}}

The config file looks fine btw:

tcp:
  routers:
    juju-test-charm-tcp-i4iy-tcp-tester-0-tcp-router:
      entryPoints:
      - test-charm-tcp-i4iy-tcp-tester-0
      rule: HostSNI(`*`)
      service: juju-test-charm-tcp-i4iy-tcp-tester-0-tcp-service
  services:
    juju-test-charm-tcp-i4iy-tcp-tester-0-tcp-service:
      loadBalancer:
        servers:
        - address: tcp-tester-0.tcp-tester-endpoints.test-charm-tcp-i4iy.svc.cluster.local:9999

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