Added the field label to the field arguments.

Initially, the field key was used as the label. In the return dictionary
has the label, so I use that value and fall back to the key if it does
not exist.

Change-Id: I39b4a7f25d8947276d3bdc3e12e728f84696a203
Co-Authored-By: Yves-Gwenaël Bourhis <yves-gwenael.bourhis@cloudwatt.com>
Merge "Added the field label to the field arguments."