Changes to Buscar Invoice por identificadores externos

for the header request parameter x-account-key, default value was added

removed the required property error from the response with the 404 status

removed the optional property error/body from the response with the 422 status

removed the optional property error/details from the response with the 422 status

api operation id get_invoices-lookup removed and replaced with lookup_invoice

api tag Invoices added

added the new optional header request parameter x-api-version

the query request parameter invoice_external_id became optional

added the non-success response with the status 401

added the non-success response with the status 403

added the non-success response with the status 429

the response property error/code became required for the status 422

the response property error/message became required for the status 422

added the required property code to the response with the 404 status

added the required property message to the response with the 404 status