DOC: Index.get_loc Cannot Accept List-like Tolerance
The docs for `Index.get_loc` suggest that the tolerance parameter may accept both a scalar and list-like argument. However, I don't think this is actually possible:

```python
# Can only pass scalar label to unique Index, so tolerance cannot be list-like
>>> pd.Index([0, 1, 2]).get_loc(1)
1
>>> pd.Index([0, 1, 2]).get_loc([1, 1])
TypeError: '[1, 1]' is an invalid key

# Inexact matches do not work against non-unique index
>>> pd.Index([1, 1, 2]).get_loc(1.1, method='nearest')
pandas.core.indexes.base.InvalidIndexError: Reindexing only valid with uniquely valued Index objects
```

In short I don't think this method can ever return a list using inexact matches. IIUC the documented list-like `tolerance` argument is therefore invalid. 

I don't see any tests for this behavior and my assumption is it was documented as part of this methods overlap with `get_indexer`, but the documentation for `get_loc` should be updated to reflect what can actually be accepted