Fix behavior editing on LB

[ajpal]

Quick fix to the LB shared function edit page. This broke when we changed behaviors to use an id field instead of the behavior name. The page loads, but saving doesn't work
Error:

After:

Links

• jira

Testing story

Reviewer Checklist:

• Tests provide adequate coverage
• Privacy and Security impacts have been assessed
• Code is well-commented
• New features are translatable or updates will not break translations
• Relevant documentation has been added or updated
• User impact is well-understood and desirable
• Pull Request is labeled appropriately
• Follow-up work items (including potential tech debt) are tracked and linked