Merge pull request #1 from ably-forks/use-jq

Use jq instead of Ruby

Author: kennethkalmer

bin/compile

@@ -29,7 +29,7 @@ fi
 cache_get_url=$(curl -s https://api.heroku.com/apps/$SHARED_BUILD_CACHE_APP_NAME/build-metadata \
   -H "Accept: application/vnd.heroku+json; version=3.build-metadata" \
   -H "Authorization: Bearer $HEROKU_API_KEY" \
-  | ruby -e "require 'json'; print JSON[STDIN.read]['cache_get_url']")
+  | jq -r .cache_get_url)
 
 echo "Restoring shared build cache from app [$SHARED_BUILD_CACHE_APP_NAME]..."