Rating plugin changes your markup (it adds <a> tag with your title inside). So just adjust your selector like this:
$('.tooltip a').tooltipster({
interactive: true,
contentAsHTML: true,
});
See working demo.
Edit:
Since <a> tag title is removed by Tooltipster, you can use a little different selector to get tooltip text:
...
focus: function(value, link){
var tip = $('.hover-test');
tip[0].data = tip[0].data || tip.html();
tip.html($(link).parent().attr('aria-label') || 'value: '+value);
},
...
This is not very clean, but should do the job. See updated demo.