False positive in linter for unused properties
See https://framagit.org/bnjbvr/kresus/merge_requests/355#note_58143.
The build https://framagit.org/nicofrand/kresus/builds/8197 failed whereas the onChange
property IS used: https://framagit.org/bnjbvr/kresus/blob/20074ac929d3d6f05a4e1885ac3297b8e3abb6eb/client/components/charts/operations-by-amount-type-select.js#L32
Storing the property in a variable (not just using it in a method) solves the issue.