Remove BLUETOOTH_CONNECT permission for API superior 23

[rcaceiro]

Description

The bluetooth permissions are currently only used to get information about Bluetooth devices, and aren't actually needed to connect/route audio to the bluetooth device.

The callback AudioManager.registerAudioDeviceCallback since API 23, avoid the need for the BLUETOOTH_CONNECT permission. This is particularly important on API 31 and up, where the BLUETOOTH_CONNECT is a runtime permission (with a rather confusing permission message).

Breakdown

• Create a scanner interface to be able of extract logic of devices discovery
• Create a legacy implementation to be able of scan audio devices compatible with android version up to M
• Create a new modern implementation to be able of scan audio devices compatible with android version from M onwards
• Create a comparator to a sortedset to main the correct order of the devices
• Adapt the current AudioSwitch class to split and better use of this different logics
• The former AudioSwitch is now the AbstractAudioSwitch that contains the common logic
• The specifics belongs to AudioSwitch and LegacyAudioSwitch classes

Validation

• Manual validation testing the different
• Adapt the current tests

Additional Notes

https://github.com/twilio/audioswitch/issues/134 https://github.com/twilio/audioswitch/issues/118 https://github.com/twilio/audioswitch/issues/115 https://github.com/twilio/audioswitch/issues/92

Submission Checklist

• [x] The source has been evaluated for semantic versioning changes and are reflected in gradle.properties
• [x] The CHANGELOG.md reflects any feature, bug fixes, or known issues made in the source code

[davidliu]

The AudioSwitch AndroidManifest.xml currently includes BLUETOOTH_CONNECT, so that should probably be removed.