Implement missing RTP2f

[sacOO7]

• Check for missing https://sdk.ably.com/builds/ably/specification/main/features/#RTP2f implementation.
• If it doesn't exist, fix missing RTP2f same as - Fix missing RTP2f same as ably/ably-cocoa@1d2f015 and https://github.com/ably/ably-cocoa/pull/1891/files

┆Issue is synchronized with this Jira Task by Unito