Message type does not list all supported values for extras

[sync-by-unito[bot]]

See Slack here:

https://ably-real-time.slack.com/archives/C01LR5XFHFX/p1666103566844009

See also:

https://github.com/ably/sdk-api-reference/blob/main/descriptions.md#:~:text=A%20JSON%20object%20of%20arbitrary%20key%2Dvalue%20pairs%20that%20may%20contain%20metadata%2C%20and/or%20ancillary%20payloads.%20Valid%20payloads%20include%20%5Bpush%5D%7B%40link%20Push%7D%2C%20%5Bdelta%5D%7B%40link%20DeltaExtras%7D%2C%20%5Bref%5D%7B%40link%20ReferenceExtras%7D%20and%20headers.

See linked support ticket for more details.

┆Issue is synchronized with this Jira Bug by Unito