Change release page query to make sure it pulls the latest release, s…

…o that it

can skip over prerelease builds.
Use extension methods for examining the GitHub release page.

TallyCore/Web/Utility/CheckForNewRelease.cs

@@ -8,6 +8,7 @@
 using System.Threading.Tasks;
 using HtmlAgilityPack;
 using NetTally.Web;
+using NetTally.Adapters;
 
 namespace NetTally
 {
@@ -143,11 +144,16 @@ private async Task<string> GetLatestVersionString()
 
                 if (htmldoc != null)
                 {
-                    var h1ReleaseTitle = htmldoc.DocumentNode.Descendants("h1")?.FirstOrDefault(n => n.GetAttributeValue("class", "").Contains("release-title"));
+                    var latest = htmldoc.DocumentNode.GetDescendantWithClass("div", "label-latest");
 
-                    if (h1ReleaseTitle != null)
+                    if (latest != null)
                     {
-                        return GetVersionString(h1ReleaseTitle.InnerText);
+                        var releaseTitle = latest.GetDescendantWithClass("h1", "release-title");
+
+                        if (releaseTitle != null)
+                        {
+                            return GetVersionString(releaseTitle.InnerText);
+                        }
                     }
                 }
             }