Use executor for some Task handlers

Author: lfkellogg

firebase-appdistribution/src/main/java/com/google/firebase/appdistribution/impl/FirebaseAppDistributionImpl.java

@@ -385,6 +385,7 @@ private void doStartFeedback(CharSequence infoText, @Nullable Uri screenshotUri)
                 releaseIdentifier
                     .identifyRelease()
                     .addOnFailureListener(
+                        blockingExecutor,
                         e -> {
                           feedbackInProgress.set(false);
                           LogWrapper.getInstance().e("Failed to identify release", e);
@@ -400,6 +401,7 @@ private void doStartFeedback(CharSequence infoText, @Nullable Uri screenshotUri)
                             // in development-mode the releaseName might be null
                             launchFeedbackActivity(releaseName, infoText, screenshotUri)
                                 .addOnFailureListener(
+                                    blockingExecutor,
                                     e -> {
                                       feedbackInProgress.set(false);
                                       LogWrapper.getInstance()