release-22.1: sql: turn off plan sampling by default

[maryliag]

Backport 1/1 commits from #88343.

/cc @cockroachdb/release

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Previously, we were sampling plans for fingerprints and saving to statement_statistics tables. Now that we are saving plan hash and plan gist (that allow us to decode back to the plan) we are no longer using the sampled plan anywhere. Since this is a heavy opperation, we are turning it off by default, but changing the default value of sql.metrics.statement_details.plan_collection.enabled to false.
If we don't receive feedback about turning it back on, we can remove this sampling entirely.

Partially addresses #77944

Release note (sql change): Change the default value of sql.metrics.statement_details.plan_collection.enabled to false, since we no longer use this information
anywhere.

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Release justification: low risk, high benefit change

[blathers-crl]

Thanks for opening a backport.

Please check the backport criteria before merging:

• Patches should only be created for serious issues or test-only changes.
• Patches should not break backwards-compatibility.
• Patches should change as little code as possible.
• Patches should not change on-disk formats or node communication protocols.
• Patches should not add new functionality.
• Patches must not add, edit, or otherwise modify cluster versions; or add version gates.

If some of the basic criteria cannot be satisfied, ensure that the exceptional criteria are satisfied within.

• 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.
• The PM and TL on the team that owns the changed code have signed off that the change obeys the above rules.

Add a brief release justification to the body of your PR to justify this backport.

Some other things to consider:

• What did we do to ensure that a user that doesn’t know & care about this backport, has no idea that it happened?
• Will this work in a cluster of mixed patch versions? Did we test that?
• If a user upgrades a patch version, uses this feature, and then downgrades, what happens?

[cockroach-teamcity]

This change is 

[yuzefovich]

Reviewed 8 of 8 files at r1, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @maryliag)