Fixed signing issue for newer versions of android.

[Hippi3Hack3r]

Jarsigner does something weird with newer versions of the android sdk causing the app to refuse to install with this error:

Targeting R+ (version 30 and above) requires the resources.arsc of installed APKs to be stored uncompressed and aligned on a 4-byte boundary]

I replaced the jarsigner code to use apksigner instead.