Refactor flat_buffer

include/boost/beast/core/flat_buffer.hpp

@@ -396,7 +396,6 @@ public:
     /// The ConstBufferSequence used to represent the readable bytes.
     using const_buffers_type = net::const_buffer;
 
-    /// The MutableBufferSequence used to represent the readable bytes.
     using mutable_data_type = net::mutable_buffer;
 
     /// The MutableBufferSequence used to represent the writable bytes.
@@ -438,7 +437,7 @@ public:
     }
 
     /// Returns a mutable buffer sequence representing the readable bytes
-    mutable_data_type
+    mutable_buffers_type
     data() noexcept
     {
         return {in_, dist(in_, out_)};