Don't offer the BT sharing option to the user if BT is disallowed.

Disable BluetoothOppLauncherActivity component if the
UserManager#BLUETOOTH_DISALLOWED user restriction is set.

Test: cts-tradefed run cts -m CtsDevicePolicyManagerTestCases --test com.android.cts.devicepolicy.DeviceOwnerTest#testBluetoothRestriction

Bug: 32895060

Change-Id: I4316843b2858aefa750f12a8a0e940424aa21a10