drop support of adding links and external_links

Instead we are using multiple Docker Compose files to create containers
in the same Docker network.

Signed-off-by: Jakub Sokołowski <jakub@status.im>

defaults/main.yml

@@ -7,8 +7,6 @@ grafana_version: '7.3.4'
 grafana_image: 'grafana/grafana:{{ grafana_version }}'
 grafana_cont_name: '{{ grafana_service_name }}'
 grafana_cont_vol: '{{ grafana_service_path }}/data'
-grafana_cont_links: []
-grafana_cont_ext_links: []
 grafana_port: 9400
 # see: http://docs.grafana.org/installation/docker/#migration-from-a-previous-version-of-the-docker-container-to-5-1-or-later
 grafana_cont_uid: 472

templates/docker-compose.yml.j2

@@ -10,9 +10,3 @@ services:
     volumes:
       - '{{ grafana_cont_vol }}/lib:/var/lib/grafana'
       - '{{ grafana_cont_vol }}/etc:/etc/grafana'
-{% if grafana_cont_ext_links|length > 0 %}
-    external_links: {{ grafana_cont_ext_links | to_yaml }}
-{% endif %}
-{% if grafana_cont_links|length > 0 %}
-    links: {{ grafana_cont_links | to_yaml }}
-{% endif %}