docs: fix the rendering for get_dummies (#291)

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Fixes internal issue 317915956 🦕

Author: ashleyxuu

third_party/bigframes_vendored/pandas/core/reshape/encoding.py

@@ -25,6 +25,7 @@ def get_dummies(
     prepended to the value.
 
     **Examples:**
+
         >>> import bigframes.pandas as pd
         >>> pd.options.display.progress_bar = None
         >>> s = pd.Series(list('abca'))