Use local mount and drop commands onto new lines

docker-compose.override.yml

@@ -3,7 +3,12 @@ version: "3.7"
 
 services:
   jekyll:
-    command: |
+    command: >
-      jekyll serve --watch --force_polling --verbose --config _config_dev.yml --trace
+      jekyll serve \
+      --watch \
+      --force_polling \
+      --verbose \
+      --config _config_dev.yml \
+      --trace
     volumes:
-      - .:/srv/jekyll
+      - ".:/srv/jekyll"