Redis 7.0 functions support

[academe-01]

Hi,
is there any plans to add support for redis functions?

https://redis.io/topics/functions-intro

[gkorland]

See: #1813

[chayim]

@academe-01 #1813 doesn't cover all of our missing commands, I'm refreshing the list as more have entered unstable. But yes - we'd like the 4.2.0 release to include FCALL, FCALL_RO and friends. Interested in working on a PR?