[gitea] Add gitea container to smtp-relay network

gitea/docker-compose.yaml

@@ -42,6 +42,7 @@ services:
     networks:
       - gitea
       - webproxy
+      - smtp-relay
 
   db:
     image: mariadb:${mariadb_version:-10.7}
@@ -66,4 +67,6 @@ networks:
   webproxy:
     external: true
     name: webproxy
-
+  smtp-relay:
+    external: true
+    name: smtp-relay