Check for app version of WireGuard

[zner0L]

With #125 we are pinning the WireGuard version, but if WireGuard is already installed we do not update or downgrade the app. We should check for the version of WireGuard installed to ensure a known state. To implement this we need a function to read out the details of apps installed on the device.

Users experiencing issues with mismatching WireGuard version should simply remove the currently installed version from their test device and rerun the analysis as a workaround.

[baltpeter]

To implement this we need a function to read out the details of apps installed on the device.

Tracked in #127.