Update SQLAlchemy pooling link from 1.4 to 2.0

[br413]

Fixes #69164

Updates the remaining stale SQLAlchemy 1.4 documentation link in \sql_alchemy_pool_pre_ping\ config to point at SQLAlchemy 2.0 docs.

• File: \airflow-core/src/airflow/config_templates/config.yml`n- Change: \en/14/core/pooling\ -> \en/20/core/pooling`n- Doc/comment-only change; no behavior change

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Important

🛠️ Maintainer triage note for @br413 · by @potiuk · 2026-07-18 15:46 UTC

Helpful heads-up from the maintainers — please address before this PR can be reviewed:

• ❌ Pre-commit / static checks. See docs.

See the Pull Request quality criteria for details.

The ball is in your court — you've been assigned to this PR. Fix the above, then mark it Ready for review.

_{Automated triage — may be imperfect; a maintainer takes the next look.}

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[br413]

Closing this PR — the target link appears already updated on main. Will open a fresh contribution for a different Airflow docs issue.

[br413]

Superseded — no diff vs main for the original target. Contributor will open a new PR for a different issue.