Fix case mismatch in changelog

Author: smilingkylan

CHANGELOG.md

@@ -62,7 +62,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - bump ws from 6.2.2 to 6.2.3 in the npm_and_yarn group across 1 directory (https://github.com/MetaMask/react-native-webview-mm/pull/35)
 - sync with upstream v13.13.5 (https://github.com/MetaMask/react-native-webview-mm/pull/47)
 
-[unreleased]: https://github.com/MetaMask/react-native-webview-mm/compare/7872dfe...main
+[Unreleased]: https://github.com/MetaMask/react-native-webview-mm/compare/7872dfe...main
 [14.5.0]: https://github.com/MetaMask/react-native-webview-mm/compare/d93893d...7872dfe
 [14.4.0]: https://github.com/MetaMask/react-native-webview-mm/compare/bfdef1a...d93893d
 [14.3.0]: https://github.com/MetaMask/react-native-webview-mm/compare/6925354...bfdef1a