curl --request POST \
  --url https://sandbox.withclasp.com/employer_documents \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: multipart/form-data' \
  --form 'employer=<string>' \
  --form 'file=<string>' \
  --form 'name=<string>' \
  --form document_type=summary_of_benefits_and_coverage

{
  "id": "<string>",
  "employer": "<string>",
  "file": "<string>",
  "name": "<string>",
  "document_type": "summary_of_benefits_and_coverage",
  "created_at": "2023-11-07T05:31:56Z"
}