Create NotificationChannel#setVibrationEffect API

This API allows setting a VibrationEffect as the vibration for a
notification channel. Before this API, only waveform vibration patterns
with the default vibration amplitude were supported. All the other types
of vibrations defined in Android, including waveforms with varying
amplitude/frequency and primitive vibrations, were not supported.

With this API, developers can directly set a VibrationEffect (the same
object representing all vibrations in Android) to a notification
channel, meaning that notifications can benefit from a much more
diverse/nuanced set of possible notification buzzes!

Bug: 241732519
Test: unit tests

Change-Id: Ic2e3802316072ad043c34b91a9b3516dd1d4a41f