Prepare next dev version

Add unreleased entry to changelog.

Signed-off-by: thc202 <[email protected]>

Author: thc202

CHANGELOG.md

@@ -4,6 +4,8 @@ All notable changes to this GitHub action will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
+## [Unreleased]
+
 ## [0.6.0] - 2024-01-25
 ### Changed
 - Run with node20. [#29](https://github.com/zaproxy/action-api-scan/issues/29)
@@ -40,6 +42,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 First release to Marketplace.
 
+[Unreleased]: https://github.com/zaproxy/action-api-scan/compare/v0.6.0...HEAD
 [0.6.0]: https://github.com/zaproxy/action-api-scan/compare/v0.5.0...v0.6.0
 [0.5.0]: https://github.com/zaproxy/action-api-scan/compare/v0.4.0...v0.5.0
 [0.4.0]: https://github.com/zaproxy/action-api-scan/compare/v0.3.1...v0.4.0