corebluetooth: Properly raise exceptions
corebluetooth: Properly raise exceptions

Currently, `CoreBluetoothProvider._raise_error` improperly passes the exception traceback as `value` to `raise_`, causing `TypeError: instance exception may not have a separate value` to be thrown instead of the real exception.

This patch fixes that error, matching the behaviour of the BlueZ driver (https://github.com/adafruit/Adafruit_Python_BluefruitLE/blob/master/Adafruit_BluefruitLE/bluez_dbus/provider.py#L105).
adafruit/Adafruit_Python_BluefruitLE