Multiple Superadmins breaks GB_ADMIN_MODE=true

[FrostySenpai]

I added a second superadmin in the .env file like this SUPERADMINS=[123456789,987654321] and I have GB_ADMIN_MODE=true, however the bot can still be added to the group by non-superadmins.

Removing the second superadmin causes GB_ADMIN_MODE to work as intended.

Also I'm on the master branch cloned on the 2018/7/10 13:35 UTC