Fix NullPointerException (#18181)

Fixes #18180

Signed-off-by: Jacob Laursen <jacob-github@vindvejr.dk>

bundles/org.openhab.binding.bluetooth.bluez/src/main/java/org/openhab/binding/bluetooth/bluez/internal/BlueZBluetoothDevice.java

@@ -220,7 +220,7 @@ private void ensureConnected() {
         }
         for (BluetoothGattService service : dev.getGattServices()) {
             for (BluetoothGattCharacteristic c : service.getGattCharacteristics()) {
-                if (c.getUuid().equalsIgnoreCase(uuid)) {
+                if (uuid.equalsIgnoreCase(c.getUuid())) {
                     return c;
                 }
             }