Add coverage for StopTetheringCallback default methods

StopTetheringCallback implements no-op default methods, so call these explicitly in the CTS test to satisfy the coverage linter.

Bug: 385014495
Bug: 385278741
Test: build
Change-Id: Ife938fc5acb6635f201cfb0dadccb601e513c929
diff --git a/tests/cts/net/util/java/android/net/cts/util/CtsTetheringUtils.java b/tests/cts/net/util/java/android/net/cts/util/CtsTetheringUtils.java
index 75b2814..27cba3a 100644
--- a/tests/cts/net/util/java/android/net/cts/util/CtsTetheringUtils.java
+++ b/tests/cts/net/util/java/android/net/cts/util/CtsTetheringUtils.java
@@ -160,11 +160,15 @@
         @Override
         public void onStopTetheringSucceeded() {
             mHistory.add(new CallbackValue.OnStopTetheringSucceeded());
+            // Call the parent method so that the coverage linter sees it: http://b/385014495
+            TetheringManager.StopTetheringCallback.super.onStopTetheringSucceeded();
         }
 
         @Override
         public void onStopTetheringFailed(final int error) {
             mHistory.add(new CallbackValue.OnStopTetheringFailed(error));
+            // Call the parent method so that the coverage linter sees it: http://b/385014495
+            TetheringManager.StopTetheringCallback.super.onStopTetheringFailed(error);
         }
 
         /**