DOC Fix docs of default values in _estimator_hhtml_repr
@@ -20,7 +20,7 @@ class _VisualBlock:
estimators.
If kind == 'single', then `estimators` is a single estimator.
- names : list of str
+ names : list of str, default=None
If kind != 'single', then `names` corresponds to estimators.
If kind == 'single', then `names` is a single string corresponding to
the single estimator.
