@Override
    public <T> Map<String, Object> offset(Map<String, T> partition) {
        return offsets(Collections.singletonList(partition)).get(partition);
    }
Implementation of OffsetStorageReader. Unlike {@link OffsetStorageWriter} which is implemented
directly, the interface is only separate from this implementation because it needs to be
included in the public API package.
connect/runtime/src/main/java/org/apache/kafka/connect/storage/OffsetStorageReaderImpl.java