Updated CHANGELOG to 7.15.0

Author: ezimuel

CHANGELOG.md

@@ -1,3 +1,19 @@
+## Release 7.15.0
+
+- Updated endpoints for Elasticsearch 7.15.0
+  [995f6d4](https://github.com/elastic/elasticsearch-php/commit/995f6d4bde7de76004e95d7a434b1d59da7a7e75)
+
+## Release 7.14.0
+
+- Usage of psr/log version 2
+  [#1154](https://github.com/elastic/elasticsearch-php/pull/1154)
+- Update search iterators to send `scroll_id` inside the request body
+  [#1134](https://github.com/elastic/elasticsearch-php/pull/1134)
+- Added the `ingest.geoip.downloader.enabled=false` setting for ES
+  [5867351](https://github.com/elastic/elasticsearch-php/commit/586735109dc18f22bfdf3b73ab0621b37e857be1)
+- Removed phpcs for autogenerated files (endpoints)
+  [651c57b](https://github.com/elastic/elasticsearch-php/commit/651c57b2e6bf98a0fd48220949966e630e5a804a)
+
 ## Release 7.13.1
 
 - Added port in url for trace and logger messages