test(text-to-speech-v1): update ITs

Author: kevinkowa

text-to-speech/src/test/java/com/ibm/watson/text_to_speech/v1/TextToSpeechTest.java

@@ -901,7 +901,6 @@ public void testAddCustomPromptWOptions() throws Throwable {
             .promptId("testString")
             .metadata(promptMetadataModel)
             .file(TestUtilities.createMockStream("This is a mock file."))
-            .filename("testString")
             .build();
 
     // Invoke operation with valid options model (positive test)

text-to-speech/src/test/java/com/ibm/watson/text_to_speech/v1/model/AddCustomPromptOptionsTest.java

@@ -42,15 +42,13 @@ public void testAddCustomPromptOptions() throws Throwable {
             .promptId("testString")
             .metadata(promptMetadataModel)
             .file(TestUtilities.createMockStream("This is a mock file."))
-            .filename("testString")
             .build();
     assertEquals(addCustomPromptOptionsModel.customizationId(), "testString");
     assertEquals(addCustomPromptOptionsModel.promptId(), "testString");
     assertEquals(addCustomPromptOptionsModel.metadata(), promptMetadataModel);
     assertEquals(
         IOUtils.toString(addCustomPromptOptionsModel.file()),
         IOUtils.toString(TestUtilities.createMockStream("This is a mock file.")));
-    assertEquals(addCustomPromptOptionsModel.filename(), "testString");
   }
 
   @Test(expectedExceptions = IllegalArgumentException.class)