code: function prepareHeaders(endpointSchema) {
    const isSendInHeader = p => p.in === 'header';
    const parameters = endpointSchema.parameters || [];
    const headerParameters = parameters.filter(isSendInHeader);
    return convertParameters(headerParameters);
  }
docs: Imports insomnia definitions of header parameters.
  
  @param {Object} endpointSchema - OpenAPI 3 endpoint schema
  @returns {Object[]} array of parameters definitions