chore: remove unused typedef CreateDownloadPathCallback (#42967)

chore: remove unused typedef ElectronDownloadManagerDelegate::CreateDownloadPathCallback

use was removed in e3c580e9

Co-authored-by: trop[bot] <37223003+trop[bot]@users.noreply.github.com>
Co-authored-by: Charles Kerr <[email protected]>

shell/browser/electron_download_manager_delegate.h

@@ -20,9 +20,6 @@ namespace electron {
 class ElectronDownloadManagerDelegate
     : public content::DownloadManagerDelegate {
  public:
-  using CreateDownloadPathCallback =
-      base::RepeatingCallback<void(const base::FilePath&)>;
-
   explicit ElectronDownloadManagerDelegate(content::DownloadManager* manager);
   ~ElectronDownloadManagerDelegate() override;