docs(rtd): removed reference to Ubuntu Pro beta services

[AnneCYH]

There are no longer any beta services in Ubuntu Pro and should be removed.
https://documentation.ubuntu.com/pro-client/en/latest/explanations/status_columns/#with-pro-subscription-attached

Proposed Commit Message

<type>(optional scope): <summary>  # no more than 72 characters

A description of what the change being made is and why it is being
made if the summary line is insufficient.  This should be wrapped at
72 characters.

If you need to write multiple paragraphs, feel free.

Fixes GH-NNNNN (GitHub Issue number. Remove line if irrelevant)
LP: #NNNNNN (Launchpad bug number. Remove line if irrelevant)

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Merge type

• Squash merge using "Proposed Commit Message"
• Rebase and merge unique commits. Requires commit messages per-commit each referencing the pull request number (#<PR_NUM>)

[AnneCYH]

https://documentation.ubuntu.com/pro-client/en/latest/explanations/status_columns/#with-pro-subscription-attached

There are no beta services and the status is limited to 3 outputs. So I suggest removing this section.
Thanks.

[blackboxsw]

I confirmed as well the Ubuntu Pro client changes regarding beta support. While they'll keep the --beta flag available and ignored, so will we as more beta services could be created in the future and the CLI and API continue to support that --beta flag or enable_beta service options.

[AnneCYH]

hi @blackboxsw ,

So would you propose keeping the Beta section but as an example with a 'mock' beta service?
Or just remove the section completely?

If there are beta services in future it would be unnecessary to keep adding / removing this section.
But I'm just wary about putting Real-time Ubuntu here since it's no longer in beta.

[blackboxsw]

Thank you for this proposal @AnneCYH. One thing I think we should add is fixes to the text in both doc/module-docs/cc_ubuntu_pro/data.yaml dropping example6.yaml link and the related file and renaming example7.yaml -> example6.yaml. You can see the rendered content at https://docs.cloud-init.io/en/latest/reference/modules.html#ubuntu-pro in the Examples tab.

Testing the rendered example content can be performed with
tox -e doc; xdg-open doc/rtd_html/reference/modules.html

[github-actions]

Hello! Thank you for this proposed change to cloud-init. This pull request is now marked as stale as it has not seen any activity in 14 days. If no activity occurs within the next 7 days, this pull request will automatically close.

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