feat(monitoring): general fixup

- added healthcheck for every service
- added nginx second "server" block for monitoring
    all monitoring services are now behind this nginx reverse proxy
- fixed logging driver not present for chat service

monitoring/prometheus/prometheus.yml

@@ -17,10 +17,10 @@ scrape_configs:
 
     static_configs:
       - targets:
-          - http://nginx/monitoring/ok
+          - http://nginx:8080/ok
           - http://auth/monitoring
           - http://user/monitoring
-          - http://icons/monitoring
+          - http://chat/monitoring
 
     relabel_configs:
       - source_labels: [__address__]