[maps-flutter] docs publishing (#10918)

This PR adds a step to update doc configs for flutter docs.

Additionally here I consolidated pr doc creation into a separate action
that is reused in maps-ios, maps-android, maps-flutter, search-ios and
search-android.

cc @mapbox/maps-android
cc @mapbox/sdk-platform
cc @mapbox/maps-ios
cc @mapbox/maps-flutter

GitOrigin-RevId: f64e2e06d81d98d6aa6b98d4191968f2bfaed777

Author: evil159