Pontoon: Update Sorbian, Upper (hsb) localization of Firefox Screenshots
Pontoon: Update Sorbian, Upper (hsb) localization of Firefox Screenshots

Localization authors:
- Michael Wolf <milupo@sorbzilla.de>

mozilla-services/screenshots,mozilla-services/pageshot,mozilla-services/screenshots,mozilla-services/screenshots,mozilla-services/pageshot,mozilla-services/screenshots,mozilla-services/pageshot,mozilla-services/pageshot