[#8348] update mongo version to latest in docker files
diff --git a/docker-compose-prod.yml b/docker-compose-prod.yml
index 19bcfaf..58c10fb 100644
--- a/docker-compose-prod.yml
+++ b/docker-compose-prod.yml
@@ -85,7 +85,7 @@
     restart: always
 
   mongo:
-    image: mongo:3.4
+    image: mongo:4.2
     ports:
       - "127.0.0.1:27017:27017"
     volumes:
diff --git a/docker-compose.yml b/docker-compose.yml
index 9741b93..6fbf5d0 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -52,7 +52,7 @@
       - /allura-data/solr:/opt/solr/server/solr/allura/data
 
   mongo:
-    image: mongo:3.4
+    image: mongo:4.2
     ports:
       - "27017:27017"
     volumes: