fixup doctest

Author: jhamman

docs/user-guide/config.rst

@@ -44,7 +44,7 @@ This is the current default configuration::
    >>> zarr.config.pprint()
    {'array': {'order': 'C',
               'write_empty_chunks': False},
-   'async': {'concurrency': 10, 'timeout': None},
+   'async': {'concurrency': 10, 'timeout': None, 'use_uvloop': True},
    'buffer': 'zarr.buffer.cpu.Buffer',
    'codec_pipeline': {'batch_size': 1,
                      'path': 'zarr.core.codec_pipeline.BatchedCodecPipeline'},