Add HesterG to maintainers (#23104)

[List of mine merged
PR](https://github.com/go-gitea/gitea/pulls?q=is%3Apr+author%3AHesterG+is%3Amerged+)

Author: HesterG

MAINTAINERS

@@ -49,4 +49,5 @@ Jason Song <i@wolfogre.com> (@wolfogre)
 Yarden Shoham <hrsi88@gmail.com> (@yardenshoham)
 Yu Tian <zettat123@gmail.com> (@Zettat123)
 Eddie Yang <576951401@qq.com> (@yp05327)
-Dong Ge <gedong_1994@163.com> (@sillyguodong)
+Dong Ge <gedong_1994@163.com> (@sillyguodong)
+Xinyi Gong <hestergong@gmail.com> (@HesterG)