Bump govuk-content-schema-test-helpers from 1.6.0 to 1.6.1
Bump govuk-content-schema-test-helpers from 1.6.0 to 1.6.1

Bumps [govuk-content-schema-test-helpers](https://github.com/alphagov/govuk-content-schema-test-helpers) from 1.6.0 to 1.6.1.
- [Release notes](https://github.com/alphagov/govuk-content-schema-test-helpers/releases)
- [Changelog](https://github.com/alphagov/govuk-content-schema-test-helpers/blob/master/CHANGELOG.md)
- [Commits](https://github.com/alphagov/govuk-content-schema-test-helpers/compare/v1.6.0...v1.6.1)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
alphagov/collections-publisher,alphagov/collections-publisher,alphagov/collections-publisher