Update CHANGELOG.md

Author: vbaranov

CHANGELOG.md

@@ -76,6 +76,7 @@
 
 ### ⚙️ Miscellaneous Tasks
 
+- Return old response format in /api/v1/health endpoint ([#11511](https://github.com/blockscout/blockscout/issues/11511))
 - Rename blob_tx_count per naming conventions ([#11438](https://github.com/blockscout/blockscout/issues/11438))
 - Follow updated response schema in interpreter microservice ([#11402](https://github.com/blockscout/blockscout/issues/11402))
 - Remove raise in case if ETHEREUM_JSONRPC_HTTP_URL is not provided ([#11392](https://github.com/blockscout/blockscout/issues/11392))