Merge pull request #1419 from TestCentric/issue-1414-2

Fix crash opening File menu when no project is loaded

Author: rowo360

src/GuiRunner/TestModel/TestModel.cs

@@ -159,7 +159,7 @@ public IEnumerable<string> ResultFormats
         /// </summary>
         public TestCentricProject TestCentricProject { get; set; }
 
-        public TestPackage TopLevelPackage => TestCentricProject.TopLevelPackage;
+        public TestPackage TopLevelPackage => TestCentricProject?.TopLevelPackage;
 
         public bool IsProjectLoaded => TestCentricProject != null;