PR #96295 - changefeedccl: Rename and remove CDC functions

[cockroach-teamcity]

Exalate commented:

Related PR: cockroachdb/cockroach#96295
Commit: cockroachdb/cockroach@5265347
Epic: https://cockroachlabs.atlassian.net/browse/CRDB-17161
Fixes: cockroachdb/cockroach#92482

---

Release note (enterprise change): Deprecate and replace some of the
changefeed specific functions made available in preview mode in 22.2
release. While these functions are deprecated, old changefeed
transformations should continue to function properly.
Customers are encouraged to closely monitor their changefeeds
created during upgrade. While effort was made to maintain backward
compatability, the updated changefeed transformation may produce
slightly different output (different column names, etc).

Jira Issue: DOC-6954

[kathancox]

Work was done here: #16599