add unit test for hasWitnessSignature

Author: CodeNinjaEvan

src/test/java/org/tron/core/capsule/BlockCapsuleTest.java

@@ -119,6 +119,15 @@ public void testGetInsHash() {
         Sha256Hash.wrap(blockCapsule0.getParentHashStr()));
   }
 
+  @Test
+  public void testHasWitnessSignature() {
+
+    Assert.assertFalse(blockCapsule0.hasWitnessSignature());
+    blockCapsule0
+        .sign(ByteArray.fromHexString(Args.getInstance().getLocalWitnesses().getPrivateKey()));
+    Assert.assertTrue(blockCapsule0.hasWitnessSignature());
+  }
+
   @Test
   public void testGetTimeStamp() {
     Assert.assertEquals(1234L, blockCapsule0.getTimeStamp());