Drop duplicative description

The same content is in `summary`. So no need to add this in two fields.
Just use `summary` as is done for simpler metadata cases.

Author: jakirkham

conda/recipes/jupyterlab-nvdashboard/meta.yaml

@@ -49,5 +49,3 @@ about:
   license_family: BSD
   license_file: ../../../LICENSE
   summary: A JupyterLab extension for displaying dashboards of GPU usage
-  description: |
-    A JupyterLab extension for displaying dashboards of GPU usage.