Draft: Enable Loki as a replacement for Elasticsearch when `enable_loki` is set.

Note, it is not possible to have both Loki and Elasticsearch enabled, so enable_elasticsearch must be disabled, when enable_loki is enabled.

roles/log-collector/templates/loki-config.yaml.j2

 auth_enabled: false
 
 server:
-  http_listen_address: 127.0.0.1
   http_listen_port: 3100
-  grpc_listen_address: 127.0.0.1
   grpc_listen_port: 9095
 
 ingester: