8373632: Some sound tests failing in CI due to lack of sound key

Reviewed-by: iris

test/jdk/javax/sound/midi/Sequencer/Looping.java

@@ -36,7 +36,7 @@ import javax.sound.midi.Track;
  * @test
  * @bug 4204105
  * @summary RFE: add loop() method(s) to Sequencer
- * @key intermittent
+ * @key sound
  */
 public class Looping {
 

test/jdk/javax/sound/sampled/Clip/IsRunningHang.java

@@ -36,6 +36,7 @@ import javax.sound.sampled.LineUnavailableException;
 /**
  * @test
  * @bug 8156169
+ * @key sound
  * @run main/othervm/timeout=300 IsRunningHang
  */
 public final class IsRunningHang {

test/jdk/javax/sound/sampled/DataLine/LongFramePosition.java

@@ -29,6 +29,7 @@ import javax.sound.sampled.SourceDataLine;
 /**
  * @test
  * @bug 5049129
+ * @key sound
  * @summary DataLine.getLongFramePosition
  */
 public class LongFramePosition {

test/jdk/javax/sound/sampled/DirectAudio/bug6372428.java

@@ -31,6 +31,7 @@ import javax.sound.sampled.TargetDataLine;
 /*
  * @test
  * @bug 6372428
+ * @key sound
  * @summary playback and capture doesn't interrupt after terminating thread that
  *          calls start()
  * @run main bug6372428