Fix manage views layout

Author: javiercn

src/UI/Areas/Identity/Pages/Account/Manage/_Layout.cshtml

@@ -1,5 +1,12 @@
 @{ 
-    Layout = "/Areas/Identity/Pages/_Layout.cshtml";
+    if (ViewData.TryGetValue("ParentLayout", out var parentLayout))
+    {
+        Layout = (string)parentLayout;
+    }
+    else
+    {
+        Layout = "/Areas/Identity/Pages/_Layout.cshtml";
+    }
 }
 
 <h2>Manage your account</h2>

src/UI/Areas/Identity/Pages/Account/Manage/_ViewStart.cshtml

@@ -0,0 +1,7 @@
+@{
+    if (Layout != "_Layout")
+    {
+        ViewData["ParentLayout"] = Layout;
+        Layout = "./_Layout.cshtml";
+    }
+}