release-23.2: roachtest: bump GC TTL on source and dest tenant ranges for weekly roachtest

[blathers-crl]

Backport 1/1 commits from #113501 on behalf of @adityamaru.

/cc @cockroachdb/release

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Previously, the kv50 weekly roachtest would take >4 hours, the default GC TTL, to complete replication and cutover. Thus, by the time fingerprinting would run some of the keys would already be under the GCThreshold before the FP machinery got a chance to write a PTS. To work around this we bump the GC TTL on the source and dest tenant ranges to 12 hours, the timeout of the roachtest.

Fixes: #112823
Release note: None

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Release justification: Test-only change.

[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.
• Backports should not change on-disk formats or node communication protocols.
• Backports should not add new functionality (except as defined
  here).
• Backports must not add, edit, or otherwise modify cluster versions; or add version gates.
• All backports must be reviewed by the owning areas TL and one additional
  TL. For more information as to how that review should be conducted, please consult the backport
  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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  channel (#db-backports-point-releases or #db-backports-XX-X-release) for awareness and discussion.

Also, please add a brief release justification to the body of your PR to justify this
backport.

[cockroach-teamcity]

This change is 

[github-actions]

Reminder: it has been 3 weeks please merge or close your backport!

[stevendanna]

Sorry I missed this. Seems reasonable to me if we still think it is important to backport.

[github-actions]

Reminder: it has been 3 weeks please merge or close your backport!

[yuzefovich]

Friendly ping: @stevendanna @msbutler is this something we want to merge?

[github-actions]

Reminder: it has been 3 weeks please merge or close your backport!

[stevendanna]

@msbutler I think we haven't seen this fail in a while? Perhaps we just close it for now?

[msbutler]

sgtm