Remove useless PRODUCTION var for webpack CodiMD

roles/codimd/handlers/main.yml

@@ -2,7 +2,7 @@
 # Build front-end bundle
 # This can take very long and requires > 2GB of RAM
 - name: Build front-end for CodiMD
-  command: NODE_ENV="production" yarn run build
+  command: yarn run build
   args:
     chdir: /var/local/codimd/codimd
   become: true