docs: Remove old header from changelog (#65)

Author: ThetaSinner

CHANGELOG.md

@@ -22,12 +22,6 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 ### First-time Contributors
 
 - @holochain-release-automation2 made their first contribution in [#58](https://github.com/holochain/hc-http-gw/pull/58)
-# Changelog
-
-All notable changes to this project will be documented in this file.
-
-The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
-and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [0.2.0] - 2025-07-09