feat(tem): new attachments (#5623)

Author: ldecarvalho-doc

pages/transactional-email/reference-content/tem-capabilities-and-limits.mdx

@@ -66,6 +66,11 @@ The attachments available are the following:
 | ZIP**                        | `application/zip`          |
 | P7C, P7M                         | `application/pkcs7-mime`          |
 | P10                       | `application/pkcs10`          |
+| WAV                          | `audio/wav`          |
+| MP3                      | `audio/mpeg`          |
+| DOC                         | `application/msword`          |
+| DOCX                     | `application/vnd.openxmlformats-officedocument.wordprocessingml.document`          |
+
 
 ** - Available only with the [Scale plan](/transactional-email/how-to/manage-tem-plans).