Description of problem:
An error occurs on editing health checks when request type `Container Command` is selected from the dropdown.


Steps to reproduce:
1. Right-Click on a node on Topology having health checks added
2. Select `Edit Health Checks`
3. In the probe form, try selecting `Container Command`

Actual Results:
the page fails to load and a Type error is logged in the browser's console

Expected Results:
the probe form should load successfully