Remove 'Contents' section from the Configuration Manual (#13438)

Fixes: #13053

Author: dklimpel

changelog.d/13438.doc

@@ -0,0 +1 @@
+Remove redundant 'Contents' section from the Configuration Manual. Contributed by @dklimpel.

docs/usage/configuration/config_documentation.md

@@ -72,49 +72,6 @@ apply if you want your config file to be read properly. A few helpful things to
   In addition, each setting has an example of its usage, with the proper indentation
   shown.
 
-## Contents
-[Modules](#modules)
-
-[Server](#server)
-
-[Homeserver Blocking](#homeserver-blocking)
-
-[TLS](#tls)
-
-[Federation](#federation)
-
-[Caching](#caching)
-
-[Database](#database)
-
-[Logging](#logging)
-
-[Ratelimiting](#ratelimiting)
-
-[Media Store](#media-store)
-
-[Captcha](#captcha)
-
-[TURN](#turn)
-
-[Registration](#registration)
-
-[API Configuration](#api-configuration)
-
-[Signing Keys](#signing-keys)
-
-[Single Sign On Integration](#single-sign-on-integration)
-
-[Push](#push)
-
-[Rooms](#rooms)
-
-[Opentracing](#opentracing)
-
-[Workers](#workers)
-
-[Background Updates](#background-updates)
-
 ## Modules
 
 Server admins can expand Synapse's functionality with external modules.