It’s not a ‘loyalty oath’. It’s a state law prohibiting contracts with organizations that participate in Israel BDS. Many states have such laws.
Sure sounds like a loyalty oath to me.
Keep in mind that the article says nothing about a distinction between the performance of her duties on the job as an employee of a government entity and her private, off-the-job activity.
Like it or not, she ought to be free to boycott Israel, and to call for others to boycott Israel, as much as she likes when it doesn't involve her official duties.