chore: fix some mypy errors #497

Job	Run time
android_test (test/functional/android/appium_service_tests.py test/functional/android/chrome_test...	4m 22s
ios_test (test/functional/ios/safari_tests.py, func_test_ios1)	9m 32s
flutter_e2e_test (ubuntu-latest, flutter-android)	5m 26s
flutter_e2e_test (macos-14, flutter-ios)	11m 6s
	30m 26s

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