Fix the issue where gatt.disconnect() may throw a SecurityException

[LuoPeiQin]

Fix the following Firebase crash:

Fatal Exception: java.lang.SecurityException: Need BLUETOOTH_PRIVILEGED permission: Neither user 10049 nor current process has android.permission.BLUETOOTH_PRIVILEGED.
       at android.os.Parcel.createExceptionOrNull(Parcel.java:2439)
       at android.os.Parcel.createException(Parcel.java:2423)
       at android.os.Parcel.readException(Parcel.java:2406)
       at android.os.Parcel.readException(Parcel.java:2348)
       at android.bluetooth.IBluetoothGatt$Stub$Proxy.clientDisconnect(IBluetoothGatt.java:2526)
       at android.bluetooth.BluetoothGatt.disconnect(BluetoothGatt.java:1005)
       at no.nordicsemi.android.ble.BleManagerHandler.internalDisconnect(BleManagerHandler.java:813)
       at no.nordicsemi.android.ble.BleManagerHandler.onRequestTimeout(BleManagerHandler.java:1717)
       at no.nordicsemi.android.ble.TimeoutableRequest.lambda$notifyStarted$0(TimeoutableRequest.java:230)
       at no.nordicsemi.android.ble.BleManagerHandler$3.run(BleManagerHandler.java:1738)
       at java.util.TimerThread.mainLoop(Timer.java:562)
       at java.util.TimerThread.run(Timer.java:512)

[CLAassistant]

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