Suppressing null reference exception warning

Author: lord-executor

src/SampleApplication/Views/Home/Index.cshtml

@@ -15,7 +15,7 @@
     <li>
         Environment Variables:
         <ul>
-            @foreach (var key in ((System.Collections.IDictionary)ViewData["Environment"]).Keys)
+            @foreach (var key in ((System.Collections.IDictionary)ViewData["Environment"])!.Keys)
             {
                 <li>@key = @(((System.Collections.IDictionary)ViewData["Environment"])[key])</li>
             }

src/SampleApplication/Views/Home/Memory.cshtml

@@ -13,7 +13,7 @@
 
 <h2>Services</h2>
 <ul>
-    @foreach (var key in ((System.Collections.IDictionary)ViewData["ServiceReferences"]).Keys)
+    @foreach (var key in ((System.Collections.IDictionary)ViewData["ServiceReferences"])!.Keys)
     {
         <li>@key = @(((System.Collections.IDictionary)ViewData["ServiceReferences"])[key])</li>
     }