Brief summary of the bug. What is it ? Where is it ?

It is possible to set a target value on multi aggregations reports with variable view

Steps to reproduce:

• Create a new report with variable view
• Add extra aggregations (e.g. max, median)
• Open the configuration popover

Actual result:

• It is possible to set the target value

Expected result:

• Target value cannot be set on multi aggregation variable reports.