add hellogithub badge (oceanbase#426)

### What problem were solved in this pull request?

Issue Number: close oceanbase#424
add hello github badge

README.md

@@ -5,6 +5,7 @@
 [![Chinese Doc](https://img.shields.io/badge/文档-简体中文-blue)](https://oceanbase.github.io/miniob/)
 [![MiniOB stars](https://img.shields.io/badge/dynamic/json?color=blue&label=stars&query=stargazers_count&url=https%3A%2F%2Fapi.github.com%2Frepos%2Foceanbase%2Fminiob)](https://github.com/oceanbase/miniob)
 [![Coverage Status](https://codecov.io/gh/oceanbase/miniob/branch/main/graph/badge.svg)](https://codecov.io/gh/oceanbase/miniob)
+[![HelloGitHub](https://abroad.hellogithub.com/v1/widgets/recommend.svg?rid=62efc8a5bbb64a9fbb1ebb7703446f36&claim_uid=AptH8D2YM3rCGL9&theme=small)](https://hellogithub.com/repository/62efc8a5bbb64a9fbb1ebb7703446f36)
 
 </div>