docs: fix version numbers

changelog.md

@@ -1,11 +1,11 @@
 # Changelog
 
-# 1.2.1 2023-07-30
+# 1.1.2 2023-07-30
 
 - **fix:** elections sometimes electing >1 leader (see [#176](https://github.com/microsoft/etcd3/issues/176))
 - **fix:** a race condition in Host.resetAllServices (see [#182](https://github.com/microsoft/etcd3/issues/182))
 
-## 1.2.0 2023-07-28
+## 1.1.1 2023-07-28
 
 - **fix:** leases revoked or released before grant completes leaking
 - **chore:** update dependencies