jQuery script to get review score not working b/c of Volvo secuirty

I tried to make a script to get the review score of a steam app - for example, get_review_score(220) should return 96.

function get_review_score(appID){
        var returnData;
        $.ajax({
            url: ("http://store.steampowered.com/app/"+appID),
            success: function(data){
                returnData=($(".responsive_reviewdesc",data));
            }
        });
        return parseFloat(returnData.text());
    }

But I get this security error:

Refused to connect to 'http://store.steampowered.com/app/220' because it violates the following Content Security Policy directive: "connect-src 'self' http://steamcommunity.com https://steamcommunity.com https://api.steampowered.com/".