Use the same image all over the place

Closes #48.

docker-compose.prod.yml

@@ -4,7 +4,9 @@ version: "3.8"
 services:
   jekyll:
     image: decentral1se/autonomic.zone:latest
-    command: bundle exec jekyll serve --host 0.0.0.0 --trace
+    command: |
+      bundle exec
+        jekyll serve --host 0.0.0.0 --trace
     environment:
       JEKYLL_ENV: production
     networks:

docker-compose.yml

@@ -3,8 +3,10 @@ version: "3.8"
 
 services:
   jekyll:
-    image: "jekyll/jekyll:4"
-    command: jekyll serve --watch --force_polling --trace
+    image: decentral1se/autonomic.zone:latest
+    command: |
+      bundle exec
+        jekyll serve --watch --host 0.0.0.0 --force_polling --trace
     volumes:
       - ".:/srv/jekyll"
     ports: