ResponseCache attribute on RazorPages Error handler method should be moved to model

Fixes dotnet/aspnetcore#553

Commit migrated from dotnet/aspnetcore@e403187be3

src/Microsoft.DotNet.Web.Spa.ProjectTemplates/content/Angular-CSharp/Pages/Error.cshtml.cs

@@ -8,13 +8,13 @@ using Microsoft.AspNetCore.Mvc.RazorPages;
 
 namespace Company.WebApplication1.Pages
 {
+    [ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
     public class ErrorModel : PageModel
     {
         public string RequestId { get; set; }
 
         public bool ShowRequestId => !string.IsNullOrEmpty(RequestId);
 
-        [ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
         public void OnGet()
         {
             RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier;

src/Microsoft.DotNet.Web.Spa.ProjectTemplates/content/React-CSharp/Pages/Error.cshtml.cs

@@ -8,13 +8,13 @@ using Microsoft.AspNetCore.Mvc.RazorPages;
 
 namespace Company.WebApplication1.Pages
 {
+    [ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
     public class ErrorModel : PageModel
     {
         public string RequestId { get; set; }
 
         public bool ShowRequestId => !string.IsNullOrEmpty(RequestId);
 
-        [ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
         public void OnGet()
         {
             RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier;

src/Microsoft.DotNet.Web.Spa.ProjectTemplates/content/ReactRedux-CSharp/Pages/Error.cshtml.cs

@@ -8,13 +8,13 @@ using Microsoft.AspNetCore.Mvc.RazorPages;
 
 namespace Company.WebApplication1.Pages
 {
+    [ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
     public class ErrorModel : PageModel
     {
         public string RequestId { get; set; }
 
         public bool ShowRequestId => !string.IsNullOrEmpty(RequestId);
 
-        [ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
         public void OnGet()
         {
             RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier;