Upgrade mastodon to 4.0 #5

https://github.com/mastodon/mastodon/releases/tag/v4.0.0

worked on the dev instance, time to try it for real?

diff --git a/mastodon.yaml b/mastodon.yaml
index 04e4c36..f73889c 100644
--- a/mastodon.yaml
+++ b/mastodon.yaml
@@ -56,7 +56,7 @@ services:
         hard: -1
 
   mastodon:
-    image: tootsuite/mastodon
+    image: tootsuite/mastodon:v4.0
     container_name: mastodon
     restart: always
     #command: bash -c "rm -f /mastodon/tmp/pids/server.pid; bundle exec rails s -p 6001"
@@ -95,7 +95,7 @@ services:
       - SMTP_FROM_ADDRESS=mastodon@$DOMAIN_NAME
 
   mastodon-streaming:
-    image: tootsuite/mastodon
+    image: tootsuite/mastodon:v4.0
     restart: always
     container_name: mastodon-streaming
     environment:
@@ -128,7 +128,7 @@ services:
       - mastodon-redis
 
   mastodon-sidekiq:
-    image: tootsuite/mastodon
+    image: tootsuite/mastodon:v4.0
     restart: always
     container_name: mastodon-sidekiq
     env_file: