docs: add changelog entry

Author: DannyvdSluijs

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 - only check minProperties or maxProperties on objects ([#802](https://github.com/jsonrainbow/json-schema/pull/802))
 - replace filter_var for uri and uri-reference to userland code to be RFC 3986 compliant ([#800](https://github.com/jsonrainbow/json-schema/pull/800))
+- avoid duplicate workflow runs ([#804](https://github.com/jsonrainbow/json-schema/pull/804))
 
 ## Changed
 - replace icecave/parity with custom deep comparator ([#803](https://github.com/jsonrainbow/json-schema/pull/803))