opt: allow OrderingChoices to imply more orderings

[jseldess]

Jesse Seldess (jseldess) commented:

PR: cockroachdb/cockroach#64593

From release notes:

Increased the intelligence of the optimizer around orderings that can be provided by certain relational expressions when there are equalities between columns. This can allow the optimizer to remove unnecessary sort operations in some cases, thus improving performance. [#64593][#64593]

Jira Issue: DOC-1336