createRegistrationAttachment
inline suspend fun PinpointSmsVoiceV2Client.createRegistrationAttachment(crossinline block: CreateRegistrationAttachmentRequest.Builder.() -> Unit): CreateRegistrationAttachmentResponse
Create a new registration attachment to use for uploading a file or a URL to a file. The maximum file size is 1MiB and valid file extensions are PDF, JPEG and PNG. For example, many sender ID registrations require a signed “letter of authorization” (LOA) to be submitted.