Fix mobile "law" tab doesn't work when in budget impacts

src/lib/urls.ts

@@ -16,14 +16,12 @@ export function newSimulationUrl(displayMode: DisplayMode): string {
   const parametersQuery: URLSearchParams = new URLSearchParams()
   if (displayMode.budget) {
     parametersQuery.append("budget", "true")
-    delete displayMode.mobileLaw
   }
   if (displayMode.edit !== undefined) {
     parametersQuery.append("edit", displayMode.edit.toString())
   }
   if (displayMode.mobileLaw) {
     parametersQuery.append("law", "true")
-    delete displayMode.budget
   }
   if (
     displayMode.testCasesIndex !== undefined &&