Remove docs mentioning old, unsupported hybrid executors

[jscheffl]

While reading following Slack discussion in https://apache-airflow.slack.com/archives/C027H098M1C/p1771329330751059 I noticed that still old hybrid executors are noted in documentation. Deserves some cleaning.

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[github-actions]

Hi maintainer, this PR was merged without a milestone set.
We've automatically set the milestone to Airflow 3.1.8 based on: backport label targeting v3-1-test
If this milestone is not correct, please update it to the appropriate milestone.

This comment was generated by Milestone Tag Assistant.

[github-actions]

Backport successfully created: v3-1-test

            Note: As of [Merging PRs targeted for Airflow 3.X](https://github.com/apache/airflow/blob/main/dev/README_AIRFLOW3_DEV.md#merging-prs-targeted-for-airflow-3x)
            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](https://apache-airflow.slack.com/archives/C03G9H97MM2) Slack channel.

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                <td>v3-1-test</td>
                <td><a href="https://github.com/apache/airflow/pull/62096"><img src="https://img.shields.io/badge/PR-62096-blue" alt="PR Link"></a></td>
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[jscheffl]

Hi maintainer, this PR was merged without a milestone set. We've automatically set the milestone to Airflow 3.1.8 based on: backport label targeting v3-1-test If this milestone is not correct, please update it to the appropriate milestone.

This comment was generated by Milestone Tag Assistant.

@jason810496 very cool! Thanks!

[jason810496]

@jason810496 very cool! Thanks!

You’re welcome! It’s great to see that the bot works well and helps smoothen the release process!

[potiuk]

Indeed :) Good bot. Nice bot.