UsbPlayerTest.PrevTest implemented

src/test/java/device/usbPlayer/UsbPlayerTest.java

@@ -125,9 +125,15 @@ void louderTest(String testName, UsbPlayer inputPlay, int expectedResult) {
     static Stream<Arguments> PrevOptions() {
         UsbPlayer up1 = new UsbPlayer();
         up1.prev();
+        UsbPlayer up2 = new UsbPlayer();
+        for (int i = 1; i < up2.getPlaylist().size(); i++) {//3
+            up2.prev();
+        }
+
 
         return Stream.of(
-                Arguments.of("From first-Song to last-Song : Musik 03.mp3 ", up1, "Musik 03.mp3")
+                Arguments.of("From first-Song to last-Song : Musik 03.mp3 ", up1, "Musik 03.mp3"),
+                Arguments.of("From first-Song to second-Song(Backward) : Musik 02.mp3 ", up2, "Musik 02.mp3")
         );
     }