Drop the obsolete EnableWriteSupport configuration option

fix #654

Author: mauroservienti

docs/upgrade-guides/1.x.x-2.0.0.md

@@ -146,16 +146,12 @@ var requestId = context.RequestId;
 
 By default ServiceComposer responds only to HTTP `GET` requests, to enable write support, for example to handle `POST` requests, the following configuration can be used when adding ServiceComposer to the application:
 
-<!-- snippet: enable-write-support -->
-<a id='snippet-enable-write-support'></a>
 ```cs
 public void ConfigureServices(IServiceCollection services)
 {
     services.AddViewModelComposition(options => options.EnableWriteSupport());
 }
 ```
-<sup><a href='/src/Snippets/WriteSupport/EnableWriteSupport.cs#L10-L15' title='Snippet source file'>snippet source</a> | <a href='#snippet-enable-write-support' title='Start of snippet'>anchor</a></sup>
-<!-- endSnippet -->
 
 ## IViewModelPreviewHandler Preview
 

docs/upgrade-guides/2.0.0-2.1.0.md

@@ -17,7 +17,7 @@ public void ConfigureServices(IServiceCollection services)
     services.AddViewModelComposition(options => options.DisableWriteSupport());
 }
 ```
-<sup><a href='/src/Snippets/WriteSupport/EnableWriteSupport.cs#L20-L25' title='Snippet source file'>snippet source</a> | <a href='#snippet-disable-write-support' title='Start of snippet'>anchor</a></sup>
+<sup><a href='/src/Snippets/WriteSupport/EnableWriteSupport.cs#L9-L14' title='Snippet source file'>snippet source</a> | <a href='#snippet-disable-write-support' title='Start of snippet'>anchor</a></sup>
 <!-- endSnippet -->
 
 When write support is disabled, `ServiceComposer.AspNetCore` will only respond to get requests.

src/ServiceComposer.AspNetCore/ViewModelCompositionOptions-Obsoletes-V3.cs

@@ -1,12 +1,3 @@
 using System;
 
-namespace ServiceComposer.AspNetCore;
-
-partial class ViewModelCompositionOptions
-{
-    [Obsolete("EnableWriteSupport is obsolete. Starting v2.1.0, write support is enabled by default. Use DisableWriteSupport to disable it. It'll be considered an error in v3.0.0 and removed in v4.0.0", true)]
-    public void EnableWriteSupport()
-    {
-        throw new NotSupportedException();
-    }
-}
+namespace ServiceComposer.AspNetCore;

src/Snippets/WriteSupport/EnableWriteSupport.cs

@@ -4,17 +4,6 @@
 
 namespace Snippets.WriteSupport;
 
-public class EnableWriteSupport
-{
-    [Obsolete("This snippet is used only by an upgrade guide. The Obsolete is needed to prevent the EnableWriteSupport usage here to cause the snippet compilation to fail.")]
-    // begin-snippet: enable-write-support
-    public void ConfigureServices(IServiceCollection services)
-    {
-        services.AddViewModelComposition(options => options.EnableWriteSupport());
-    } 
-    // end-snippet
-}
-
 public class DisableWriteSupport
 {
     // begin-snippet: disable-write-support