Remove unnecessary --link flags

Warning: The --link flag is a legacy feature of Docker. It may eventually be removed. Unless you absolutely need to continue using it, we recommend that you use user-defined networks to facilitate communication between two containers instead of using --link. One feature that user-defined networks do not support that you can do with --link is sharing environmental variables between containers. However, you can use other mechanisms such as volumes to share environment variables between containers in a more controlled way. https://docs.docker.com/compose/compose-file/#links

user@host~/dev/HomelabOS grep -ir 'links:' *
roles/bulletnotes/templates/docker-compose.bulletnotes.yml.j2:    links:
roles/darksky_influx/templates/docker-compose.darksky-influx.yml.j2:    links:
roles/firefly_iii/templates/docker-compose.firefly_iii.yml.j2:    links:
roles/gitea/templates/docker-compose.gitea.yml.j2:    links:
roles/inventario/templates/docker-compose.inventario.yml.j2:    links:
roles/mashio/templates/docker-compose.mashio.yml.j2:    links:
roles/matomo/templates/docker-compose.matomo.yml.j2:    links:
roles/monicahq/templates/docker-compose.monicahq.yml.j2:    links:
roles/xfinityusageinfluxdb/templates/docker-compose.xfinityusageinfluxdb.yml.j2:    links:
roles/ownPhotos/templates/docker-compose.ownPhotos.yml.j2:    links:
roles/ownPhotos/templates/docker-compose.ownPhotos.yml.j2:    links:
roles/ownPhotos/templates/docker-compose.ownPhotos.yml.j2:    links: