[AIRFLOW-XXXX] Update .mailmap with some missing authors (#7290)

.mailmap

@@ -51,12 +51,16 @@ Kamil Breguła <mik-laj@users.noreply.github.com> <kamil.bregula@polidea.com>
 Kaveri Sharma <kaverisharma09@gmail.com>
 Kaxil Naik <kaxilnaik@apache.org>
 Kaxil Naik <kaxilnaik@apache.org> <kaxilnaik@gmail.com>
+Kousuke Saruta <sarutak@oss.nttdata.co.jp>
+Kousuke Saruta <sarutak@oss.nttdata.co.jp> <sarutak@oss.nttdata.com>
 Marcin Szymański <ms32035@gmail.com>
 Maxime Beauchemin <maxime.beauchemin@apache.org> <maxime_beauchemin@i-0963e1d9.inst.aws.airbnb.com>
 Maxime Beauchemin <maxime.beauchemin@apache.org> <maxime_beauchemin@i-a94af485.inst.aws.airbnb.com>
 Maxime Beauchemin <maxime.beauchemin@apache.org> <maxime.beauchemin@airbnb.com>
 Maxime Beauchemin <maxime.beauchemin@apache.org> <maximebeauchemin@gmail.com>
 Michał Słowikowski <michalslowikowski00@gmail.com>
+Mustafa Gök <sd.mustafagok@gmail.com>
+Mustafa Gök <sd.mustafagok@gmail.com> <gokmust@itu.edu.tr>
 Niels Zeilemaker <niels@zeilemaker.nl>
 Niels Zeilemaker <niels@zeilemaker.nl> <nielszeilemaker@godatadriven.com>
 Nikolay Kolev <nikolays@wepay.com>