BumbleBluetoothTests: Add non-connectable LeScanningTest

Add startBleScan_withNonConnectablePublicAdvertisement test, which
tests scanning of a non-connectable advertisement and verifies that
the scan result's isConnectable() field returns false.

Bug: 312883465
Flag: TEST_ONLY
Test: atest BumbleBluetoothTests:android.bluetooth.LeScanningTest
Change-Id: I7121adfa5e8e4aae086ef9d8fa4150765377744d