Remove android autofocus restriction to allow more phones to be compatible

[Tbaut]

We just had a report by a user that their phone isn't compatible with Signer. By checking more in details, the phone is only a couple years old, and runs android 8 or 9, which is definitely supported. Last I checked it runs fine on android 7.

checking a little deeper, it looks like we require the phone to support autofocus. Which this phone is not marked as supporting. This is obviously a little weird, since the phone 100% has autofocus.

We should try to remove this restriction in our manifest and see if this has any bad consequence on the building of the app.