Updates link to derivative config file in notebook
The link to the "derivatives config file" in the example notebook seems to be broken since v0.7.0.
It currently links to which doesn't exist anymore.
I updated the link to as I assume that it should link to this config file.
"source": [
"### Loading derivatives\n",
"\n",
- "By default, `BIDSLayout` objects are initialized without scanning contained `derivatives/` directories. But you can easily ensure that all derivatives files are loaded and endowed with the extra structure specified in the [derivatives config file](https://github.com/bids-standard/pybids/blob/master/bids/grabbids/config/derivatives.json):"
+ "By default, `BIDSLayout` objects are initialized without scanning contained `derivatives/` directories. But you can easily ensure that all derivatives files are loaded and endowed with the extra structure specified in the [derivatives config file](https://github.com/bids-standard/pybids/blob/master/bids/layout/config/derivatives.json):"
]
},
{
