meta: add mailmap entry for abmusse

PR-URL: #55182
Reviewed-By: Yagiz Nizipli <[email protected]>
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: Moshe Atlow <[email protected]>
Reviewed-By: Antoine du Hamel <[email protected]>

.mailmap

@@ -2,6 +2,7 @@
 Aaron Bieber <[email protected]> <[email protected]>
 Aaron Heckmann <[email protected]> <[email protected]>
 Aayush Ahuja <[email protected]>
+Abdirahim Musse <[email protected]> <[email protected]>
 Abe Fettig <[email protected]> <[email protected]>
 Abhimanyu Vashisht <[email protected]>
 Adam Langley <[email protected]> <[email protected]>