Android BLE Library v 2.4.0 beta 3

What's Changed

• State mapping fixed by @philips77 in #368
• Returning the same instance of state observers in ktx by @philips77 in #366
• Making sure then() callback is called for RemoveBond request by @philips77 in #365

Full Changelog: 2.4.0.beta02...2.4.0-beta03