Update to use api v3

index.html

@@ -171,7 +171,7 @@ <h1 data-readonly-key="UKsc30GIblRMKKN4BEPXcBNLa8bx4grU">Uptime Checkers</h1>
                     }
                 }
             };
-            httpRequest.open("GET", "https://healthchecks.io/api/v2/checks/");
+            httpRequest.open("GET", "https://healthchecks.io/api/v3/checks/");
             httpRequest.setRequestHeader("X-Api-Key", key);
             httpRequest.send();
         }