Add description to field of job

Hello,

I found here how to edit label of field of form Job Submission :
https://wpjobmanager.com/document/editing-job-submission-fields/

But how to add a HTML description to a field ?

I would like to add this text under the field “Job category”, with a link :

If the Job category you're looking for is not listed here, click here to submit a new one

Many thanks for your help