Pontoon: Update Czech (cs) localization of AMO Frontend
Pontoon: Update Czech (cs) localization of AMO Frontend

Localization authors:
- Jakub Rychlý <jrychly@jakubrychly.cz>
- Tomáš Zelina <zelitomas@gmail.com>
- Michal Stanke <mstanke@mozilla.cz>

aviarypl/mozilla-l10n-addons-frontend,tsl143/addons-frontend,aviarypl/mozilla-l10n-addons-frontend,kumar303/addons-frontend,mozilla/addons-frontend,kumar303/addons-frontend,mozilla/addons-frontend,tsl143/addons-frontend,mozilla/addons-frontend,tsl143/addons-frontend,mozilla/addons-frontend,tsl143/addons-frontend,kumar303/addons-frontend,kumar303/addons-frontend,aviarypl/mozilla-l10n-addons-frontend,aviarypl/mozilla-l10n-addons-frontend