Create JSON schema for EPA Key Contacts form

[chris-kuryak]

Summary

This ticket is to complete the backend work for the EPA Key Contacts Form.

Form information: https://www.grants.gov/forms/form-items-description/fid/674

Readme: https://github.com/HHS/simpler-grants-gov/tree/main/api/src/form_schema/forms

Form metadata: https://docs.google.com/spreadsheets/d/1nGolGAVMPgDQ3kaDwE9CtRPqfR6Eh40LG2WZyGAM8O8/edit?gid=1515759995#gid=1515759995

Acceptance criteria

• JSON Schema
• Shared JSON Schema changes