prepare release

Author: dbu

Diff for: CHANGELOG.md

@@ -1,5 +1,9 @@
 # Change Log
 
+## 1.18.1 - 2023-05-17
+
+- [#242](https://github.com/php-http/discovery/pull/242) - Better exception message when no legacy php-http message factories can be built. Also needs php-http/message-factory package and they are deprecated in favor of PSR-17 anyways.
+
 ## 1.18.0 - 2023-05-03
 
 - [#235](https://github.com/php-http/discovery/pull/235) - Deprecate HttpClientDiscovery, use Psr18ClientDiscovery instead