Docker: Fix "Failed export and unexpected container restart"

- Fixes #4089

Also this was broken too:

docker-compose exec wekandb apt-get update

because /tmp didn't exist, it was introduced by this commit:
1322c1fbbd

torodb-postgresql/docker-compose.yml

@@ -139,9 +139,6 @@ services:
     volumes:
       - /etc/localtime:/etc/localtime:ro
       - /etc/timezone:/etc/timezone:ro
-      - wekan-db:/data/db
-      - wekan-db-dump:/dump
-
   wekan:
     image: quay.io/wekan/wekan
     container_name: wekan-app
@@ -613,7 +610,6 @@ services:
     volumes:
       - /etc/localtime:/etc/localtime:ro
       - /etc/timezone:/etc/timezone:ro
-      - wekan-tmp:/tmp
 
 #---------------------------------------------------------------------------------
 # ==== OPTIONAL: SHARE DATABASE TO OFFICE LAN AND REMOTE VPN ====
@@ -646,8 +642,6 @@ volumes:
     driver: local
   mongodb-dump:
     driver: local
-  wekan-tmp:
-    driver: local
 
 networks:
   wekan-tier: