Fix reaction schedules removed on edit

What does this MR do and why?

• Fix dict key mismatch that caused reaction schedules to be purged from DB on edit.
• Resolves #728 (closed)

How to set up and validate locally

• Create a parent schedule
• Create a reaction schedule
• Edit the reaction schedule.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• Have you checked this doesn't interfere/conflict/duplicate someone elses work?
• Have you fully tested your changes?
• Have you resolved any lint issues?
• Have you assigned a reviewer?
• Have you applied correct labels?