Allow 6 digit PIN for Auth app lock

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Currently Auth lets you pick device lock, pin lock or password for app lock. Right now pin lock will only let you set a 4 digit pin. I would like to have the ability to use a 6 digit pin instead. This is less from a security standpoint and more to ease friction of migration from other authenticators which use 6 digit.

I realize there is the option to set a longer PIN by selecting password instead, but then you have to toggle the keyboard and use the tiny keys instead of the larger ones for number only input, so it's a bit of a hassle.