Fix unused file removal

CHDataManagement/Generator/Results/GenerationResults.swift

@@ -298,6 +298,10 @@ final class GenerationResults: ObservableObject {
     func requiredOutputFile(_ path: String) {
         update { self.requiredOutputFiles.insert(path) }
     }
+
+    func removeUnusedFile(_ unusedFile: String) {
+        update { self.unusedFilesInOutput.remove(unusedFile) }
+    }
 }
 
 private extension Dictionary where Value == Set<LocalizedItemId> {

CHDataManagement/Views/Generation/GenerationContentView.swift

@@ -168,7 +168,7 @@ struct GenerationContentView: View {
         guard content.storage.deleteInOutputFolder(unusedFile) else {
             return
         }
-        content.results.unusedFilesInOutput.remove(unusedFile)
+        content.results.removeUnusedFile(unusedFile)
     }
 
     private func show(page pageId: String, language: ContentLanguage? = nil) {