Update TRANSLATORS (go-gitea#5194)

Hi,
I'm the guy who translated gitea during June in Italian.
I would like to have my name added to the translators list.
I translated nearly a thousand and a half words.
Thank you.

options/locale/TRANSLATORS

@@ -12,6 +12,7 @@ Anderi Azuki <k1nzy AT outlook DOT com>
 Andrey Nering <andrey AT nering DOT com DOT br>
 Andrey Solomatin <toadron AT yandex DOT ru>
 Antoine GIRARD <sapk AT sapk DOT fr>
+Antonio Briola <briolantonio AT gmail DOT com>
 Arthur Aslanyan <arthur DOT e DOT aslanyan AT gmail DOT com>
 Aurelien Darragon <aurelien DOT darragon AT gmail DOT com>
 Barış Arda Yılmaz <ardayilmazgamer AT gmail DOT com>