Prometheus: Put External URL into alerts

coreos-config/roles/compose_project/templates/prometheus/docker-compose.yaml

@@ -5,6 +5,7 @@ services:
     restart: unless-stopped
     command:
       - '--config.file=/etc/prometheus/prometheus.yml'
+      - '--web.external-url=https://prometheus.tobiasmanske.de'
     volumes:
       - ./prometheus.yml:/etc/prometheus/prometheus.yml:ro,Z
       - prom_data:/prometheus
@@ -54,6 +55,7 @@ services:
     restart: unless-stopped
     command:
       - '--config.file=/etc/alertmanager/config.yml'
+      - '--web.external-url=https://alertmanager.tobiasmanske.de'
       - '--storage.path=/data'
 
   alertmanager-matrix: