For #6036 - Use app defined string for the cancel button
For #6036 - Use app defined string for the cancel button

This overrides the platform default and allows for the app to provide
translations for languages which don't have a translation for the cancel button
text in platform.

mozilla-mobile/focus-android,mozilla-mobile/focus-android,mozilla-mobile/focus-android,mozilla-mobile/focus-android,mozilla-mobile/focus-android,mozilla-mobile/focus-android