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[kathryn-ods]

Overview

What does this pull request do? fixes #721

How can a reviewer test or examine your changes?
check all the tests pass, build the docs and check the expected fields now show as required

Who is best placed to review it?

Closes #

Translations

• New or edited strings appearing as a result of this PR will be picked up for translation
• I've notified the translation coordinator of any new strings that will need
  translating. See the Handbook

Documentation & Release

• I've checked that the documentation builds without failing. See the Handbook
• I've thought about how and when this needs to be released. See the Handbook
• I've updated the changelog, if necessary. See the Handbook
• I've updated reference.rst to reflect any changes to schema structure or naming.
• I've added or edited any other related documentation. See the Handbook

[kathryn-ods]

@kd-ods I think this ok to merge as won't actually impact the 0.4.0 branch but tagging for a sense check when you're back. Also should we be merging this in to 0.4.0 or 0.4.1 maybe?