Spreadsheet: Properly pass parent window to Workbook

Change the parent of the WizardDialog to that of the Spreadsheet window.
Previously the WizardDialog was using the open file dialog as the
parent resulting in the csv import dialog

Userland/Applications/Spreadsheet/ImportDialog.h

@@ -56,7 +56,7 @@ private:
 };
 
 struct ImportDialog {
-    static Result<NonnullRefPtrVector<Sheet>, String> make_and_run_for(StringView mime, Core::File& file, Workbook&);
+    static Result<NonnullRefPtrVector<Sheet>, String> make_and_run_for(GUI::Window* parent, StringView mime, Core::File& file, Workbook&);
 };
 
 }