release-24.3: sql: do not use fast-path-checks if there are row-level BEFORE triggers

[blathers-crl]

Backport 1/1 commits from #133330 on behalf of @DrewKimball.

/cc @cockroachdb/release

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sql: do not inline INSERT values into checks if there are BEFORE triggers

This commit prevents a possible bug in uniqueness checks when the table has
row-level BEFORE triggers. The issue is an optimization that attempts to
inline INSERT values into the check, to avoid buffering. This inlining
logic uses the input of the INSERT operator before row-level triggers
are added, and so it does not observe any modifications made to the rows.
This could in theory result in the check failing to detect duplicates,
although I was unable to create a logictest to produce this result.

Fixes #133329

Release note: None

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Release justification: bug fix for new functionality in 24.3

[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.
• Backports should not break backwards-compatibility.
• Backports should change as little code as possible.
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• Backports should not add new functionality (except as defined
  here).
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  policy.

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.
• The new functionality is additive-only and only runs for clusters which have specifically “opted in” to it (e.g. by a cluster setting).
• New code is protected by a conditional check that is trivial to verify and ensures that it only runs for opt-in clusters. State changes must be further protected such that nodes running old binaries will not be negatively impacted by the new state (with a mixed version test added).
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• Your backport must be accompanied by a post to the appropriate Slack
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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 

[DrewKimball]

@mgartner friendly ping

[michae2]

Reviewed 3 of 3 files at r1, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @DrewKimball, @mgartner, and @rytaft)

[blathers-crl]

It looks like your PR touches production code but doesn't add or edit any test code. Did you consider adding tests to your PR?

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is dev-inf.}

[DrewKimball]

TFTR