Updates for string freeze, pre-translation

[marcellamaki]

Fixes #4068 and the items adjusted in the google doc after string review. Deletes 'context' which was extracted as a string in one case.

[radinamatic]

Yey, much better strings now!!! 👏🏽 🥇

[bjester]

This whole translator is actually just wrong! It should have been:

export const validationStrings = createTranslator('ValidationStrings', {
  msgId: {
    message: 'Missing required information',
    context:
    'An error message displayed when some information required before publishing a channel is missing, for example when a resource has no license set.',
  }
});

but it isn't even used anywhere, so I'm deleting it!