sql: override StmtTimeout to 0 for sessionless IE

[annrpom]

For queries issued by a sessionless internal executor,
we inherit values from cluster settings. This means
that setting a cluster-wide statement timeout will
impact processes that use a sessionless internal
executor: background jobs, db console, cloud sql
shell, etc. This behavior doesn't make sense in most
cases; so, this patch will override the statement timeout
to 0s (i.e. none).

For the cloud sql shell, this change makes sense as there
is a default payload request timeout applied to these
queries (5s).

Fixes: #126261
Release note (bug fix): Internally issued queries that are not
initiated within a SQL session no longer respect a statement timeout.
This includes: background jobs, queries issued by the db
console that perform introspection, and the cloud sql shell.

[cockroach-teamcity]

This change is 

[rafiss]

lgtm!

[annrpom]

TFTR! ('-')7

bors r=rafiss

[craig]

Merge conflict.

[annrpom]

bors r=rafiss

[craig]

Build succeeded:

• lint
• linux_amd64_fips_build
• macos_amd64_build
• local_roachtest_fips
• check_generated_code
• macos_arm64_build
• linux_arm64_build
• docker_image_amd64
• unit_tests
• windows_build
• examples_orms
• linux_amd64_build
• acceptance
• local_roachtest

[blathers-crl]

Based on the specified backports for this PR, I applied new labels to the following linked issue(s). Please adjust the labels as needed to match the branches actually affected by the issue(s), including adding any known older branches.

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Issue #126261: branch-release-24.2.

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[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

You might need to create your backport manually using the backport tool.

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error creating merge commit from a53bf7a to blathers/backport-release-23.2-129489: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 23.2.x failed. See errors above.

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error creating merge commit from a53bf7a to blathers/backport-release-24.1-129489: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 24.1.x failed. See errors above.

---

error creating merge commit from a53bf7a to blathers/backport-release-24.2-129489: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 24.2.x failed. See errors above.

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