release-23.2: opt: fix hints for placeholder fast path

[blathers-crl]

Backport 1/1 commits from #147368 on behalf of @mgartner.

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Fixes #147363

Release note (bug fix): A bug has been fixed that cause the optimizer to
ignore index hints when optimizing some forms of prepared statements.
This could result in one of two unexepcted behaviors: a query errors
with the message "index cannot be used for this query" when the index
can actually be used, or query using an index that does not adhere to
the hint. The hints relevant to this bug are regular index hints, e.g.,
SELECT * FROM tab@index, FORCE_INVERTED_INDEX and FORCE_ZIGZAG.

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Release justification:

[blathers-crl]

Thanks for opening a backport.

Please check the backport criteria before merging:

• Backports should only be created for serious
  issues or test-only changes.
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If your backport adds new functionality, please ensure that the following additional criteria are satisfied:

• There is a high priority need for the functionality that cannot wait until the next release and is difficult to address in another way.
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Also, please add a brief release justification to the body of your PR to justify this
backport.

[cockroach-teamcity]

This change is 

[michae2]

As discussed in slack, I think we should hold off on this one, just in case anyone's workload is using bad hints that are currently ignored.

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @DrewKimball)

[mgartner]

Agreed. backport-all was just easier 😉.