Add alter hook "content_export_translated_entity" to change basefields of translations

Made a patch which should provide the alter hook "content_export_translated_entity" after `$this->exportBaseValues` in translation condition

rerolled patch for version 1.4

I don't see much sense to introduce new hooks.

You can alter translations by using event subscriber. See ✨ Include translations to ExportEvent event, so user can alter translations too Active