Update bulkSave test to use the api

[eileenmcnaughton]

Overview

Update bulkSave test to use the API

Before

Test uses internal function

After

Test uses the API

Technical Details

@colemanw I think this makes more sense now

Comments

[civibot]

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[colemanw]

@eileenmcnaughton this looks good now. Are we ready for CRM_Core_BAO_CustomField::bulkSave to emit a deprecation warning? Or are any of your extensions using it?

[eileenmcnaughton]

@colemanw we might be using it - but I don't see that as blocking deprecation