chore: updated changelog.md

Signed-off-by: Manish Dait <daitmanish88@gmail.com>

Author: manishdait

CHANGELOG.md

@@ -7,6 +7,7 @@ This changelog is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.
 ## [Unreleased]
 
 ### Added
+- Add support for chunk message  in `TopicSubmitMessageTransaction`.
 
 ### Changed
 
@@ -52,7 +53,6 @@ This changelog is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.
 - Added `docs\sdk_developers\training\receipts.md` as a training guide for users to understand hedera receipts.
 - Add `set_token_ids`, `_from_proto`, `_validate_checksum` to TokenAssociateTransaction [#795]
 - docs: added `network_and_client.md` with a table of contents, and added external example scripts (`client.py`).
-- Add support for chunk message  in `TopicSubmitMessageTransaction`.
 
 
 ### Changed