Fix comment syntax in any.proto (#8792)

* Fix comment syntax in any.proto

Remove extra spaces which cause incorrect indentation in godoc.
Remove the "====" style title which is not rendered by godoc.

* Run ./generate_descriptor_proto.sh

csharp/src/Google.Protobuf/WellKnownTypes/Any.cs

@@ -95,7 +95,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// name "y.z".
   ///
   /// JSON
-  /// ====
+  ///
   /// The JSON representation of an `Any` value uses the regular
   /// representation of the deserialized, embedded message, with an
   /// additional field `@type` which contains the type URL. Example:

objectivec/GPBAny.pbobjc.h

@@ -112,7 +112,7 @@ typedef GPB_ENUM(GPBAny_FieldNumber) {
  *
  *
  * JSON
- * ====
+ *
  * The JSON representation of an `Any` value uses the regular
  * representation of the deserialized, embedded message, with an
  * additional field `\@type` which contains the type URL. Example:

php/src/Google/Protobuf/Any.php

@@ -53,7 +53,6 @@ use Google\Protobuf\Internal\GPBUtil;
  * in the type URL, for example "foo.bar.com/x/y.z" will yield type
  * name "y.z".
  * JSON
- * ====
  * The JSON representation of an `Any` value uses the regular
  * representation of the deserialized, embedded message, with an
  * additional field `@type` which contains the type URL. Example:

src/google/protobuf/any.proto

@@ -95,7 +95,7 @@ option objc_class_prefix = "GPB";
 //
 //
 // JSON
-// ====
+//
 // The JSON representation of an `Any` value uses the regular
 // representation of the deserialized, embedded message, with an
 // additional field `@type` which contains the type URL. Example: