update changelog for cypher mcp v0.2.3

Author: a-s-g93

servers/mcp-neo4j-cypher/CHANGELOG.md

@@ -8,6 +8,12 @@
 * Namespace option via CLI or env variables. This allows many Cypher MCP servers to be used at once.
 * Allow transport to be specified via env variables
 
+## v0.2.3
+
+### Added
+* Namespace option via CLI or env variables. This allows many Cypher MCP servers to be used at once.
+* Allow transport to be specified via env variables
+
 
 ## v0.2.2