add link to PR in CHANGELOG

Author: StijnCaerts

CHANGELOG.md

@@ -16,7 +16,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Examples folder with example docker setup for running sfes from pip [#147](https://github.com/stac-utils/stac-fastapi-elasticsearch/pull/147)
 
 ### Changed
-- Use aliases on Elasticsearch indices, add number suffix in index name.
+
+- Use aliases on Elasticsearch indices, add number suffix in index name. [#152](https://github.com/stac-utils/stac-fastapi-elasticsearch/pull/152)
+
 ### Fixed
 
 - Corrected the closing of client connections in ES index management functions [#132](https://github.com/stac-utils/stac-fastapi-elasticsearch/issues/132)