Merge pull request #249 from delegateas/issue#243_implement_formcontext.ui_methods

Update xrm_ext_9-.d.ts

Author: misoeli

src/XrmDefinitelyTyped/Resources/Extensions/xrm_ext_9-.d.ts

@@ -517,7 +517,7 @@ declare namespace Xrm {
         /**
          * Specify "dashboard"
          */
-        pageType: string;
+        pageType: "dashboard";
 
         /**
          * The ID of the dashboard to load. If you don't specify the ID, navigates to the default dashboard.