Creating a new version of the test helper

1. Merge develop into master.
2. Set the version using grunt set-version --new-version=[VERSION] (e.g., grunt set-version --new-version=1.1.0) & grunt update-version.
3. Commit the changes.
4. Make the tag, e.g. git tag -a 1.1.0 -m "1.1.0".
5. Push the tag: git push --tags
6. Merge master back to develop.
7. Add all changes from the PRs to the newly created tag https://github.com/Yoast/yoast-test-helper/releases