Skyderby.helpers.init_maps_api = function() {
    if (window.Skyderby.maps_api_ready) {
        window.Skyderby.trigger('maps_api_ready');
    } else {
        Skyderby.helpers.load_script('http://maps.googleapis.com/maps/api/js?callback=on_maps_api_ready');
    }
};

Skyderby.helpers.init_maps_api = function() {
    if (window.Skyderby.maps_api_ready) {
        window.Skyderby.trigger('maps_api_ready');
    } else {
        Skyderby.helpers.load_script('https://maps.googleapis.com/maps/api/js?callback=on_maps_api_ready');
    }
};

change maps url to https