Select component warning on submit

When form data is submitted and the server sends a successful post response for a visit,
`visit.service` and `visit.program` goes from an id (integer) to an object. This throws a Material-UI `select` warning because an object is not an expected value.

2 possible solutions:
1. hold two different state objects for the visit in mobx, one for form data/input and one for current visit/responses
2. useState for onChange values inside the component itself. this method will need extra care that the correct values are validated and submitted. first method preferred