Adapt code to Attribute class renaming

See fd#6171

changed milestone to %FusionDirectory 1.4

added PJ1802-0188 label

mentioned in commit f70aba6f

added simple-plugin label

changed due date to August 05, 2021

Hello @cchilliet

Is there some test needed here ?

Cheers

added 5m of time spent

@bmortier Just that nothing broke, the plugins test suite would be handy in this case.

added To Be Tested label

The selenium tests passed

closed

added 5m of time spent

removed due date

added Fixed label and removed To Be Tested label