@Override
    public <K, V> void forward(final K key, final V value) {
        forward(key, value, To.all());
    }
Get the punctuators scheduled so far. The returned list is not affected by subsequent calls to {@code schedule(...)}.

@return A list of captured punctuators.
streams/test-utils/src/main/java/org/apache/kafka/streams/processor/MockProcessorContext.java