Activity KPI Argo - Supprimer la ligne average past 4 years.

### Context/theme

Argo

### Other context (if applicable)

_No response_

### Describe the bug

Supprimer la ligne pointillée "Average past 4 years". Qui ne represente pas ce que je souhaiterai pour le moment.

### To reproduce

_No response_

### Expected behaviour

_No response_

### Software/browsing information

_No response_

### Other information

_No response_