Update USERS.md (facebook#8923)

Summary:
fix typo

Pull Request resolved: facebook#8923

Reviewed By: mrambacher

Differential Revision: D31003331

Pulled By: zhichao-cao

fbshipit-source-id: 00cfcac247621b8bc6d43a3d45c6a11c9dece5b0

USERS.md

@@ -113,7 +113,7 @@ LzLabs is using RocksDB as a storage engine in their multi-database distributed
 [YugabyteDB](https://www.yugabyte.com/) is an open source, high performance, distributed SQL database that uses RocksDB as its storage layer. For more information, please see https://github.com/yugabyte/yugabyte-db/.
 
 ## ArangoDB
-[ArangoDB](https://www.arangodb.com/) is a native multi-model database with flexible data models for documents, graphs, and key-values, for building high performance applications using a convenient SQL-like query language or JavaScript extensions. It uses RocksDB as its sotrage engine.
+[ArangoDB](https://www.arangodb.com/) is a native multi-model database with flexible data models for documents, graphs, and key-values, for building high performance applications using a convenient SQL-like query language or JavaScript extensions. It uses RocksDB as its storage engine.
 
 ## Milvus
 [Milvus](https://milvus.io/) is an open source vector database for unstructured data. It uses RocksDB not only as one of the supported kv storage engines, but also as a message queue.