Document effect of state-store cleanup in ResumableJobMixin

[amoghrajesh]

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Running airflow state-store clean while a task's retry_delay exceeds default_retention_days can delete a needed job identifier before the next retry reads it. The operator then silently submits a fresh job instead of reconnecting, which can duplicate work for a job still running externally. Nothing else surfaces this interaction between the two independently configured settings, so it's easy to hit without any error or warning.

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[github-actions]

Backport successfully created: v3-3-test

Note: As of Merging PRs targeted for Airflow 3.X
the committer who merges the PR is responsible for backporting the PRs that are bug fixes (generally speaking) to the maintenance branches.

In matter of doubt please ask in #release-management Slack channel.

Status	Branch	Result
✅	v3-3-test