Participant Search followup work

[MikeyManoguerra]

• remove this useEffect entirely. now that we are not using the store based params, the first search returns all participants. Also, There is no need to make this call when the component is mounted. Eventually use a MUI loading component, and a more descriptive no results display

https://github.com/CodeForPhilly/prevention-point/blob/3233440cb4ed9aa8ca124c22ae24bbfb5133e44c/frontend/src/views/ParticipantList.js#L57

• Set the participantSearch initial values to empty strings, not ternary

• remove participantStore.params object

• make the anonymous onSubmit fn async, then await participantStore.getParticipants

• create src/validation and validation/index.js move the vaidation schema into this file, call it searchSchema
  

• rename this component MainLayout https://github.com/CodeForPhilly/prevention-point/blob/3233440cb4ed9aa8ca124c22ae24bbfb5133e44c/frontend/src/layouts/MainLayout.js#L48