QualifiedNameProvider does not provide qualified name for keyword arguments.

for a function like:

```python
def fun(arg):
pass
```

the fully qualified name for `arg` will be `fun..arg`, but for any call to the function that chooses to call it using a keyword argument:

```python
fun(arg=1)
```

no metadata is found for `arg`. It seems like the necessary scope information would be there, but I suspect the visitor used by the QN provider does not traverse far enough into the arg node to hit arg.keyword, maybe?