Add blog post and date to required workflow beta note (#40554)

Co-authored-by: Siara <[email protected]>
Co-authored-by: Ben Ahmady <[email protected]>

Author: 3 people

data/reusables/actions/workflows/required-workflow-beta.md

@@ -1,5 +1,5 @@
 {% note %}
 
-**Note:** Required workflows for {% data variables.product.prodname_actions %} are in private beta and are not available for new signups.
+**Note:** Required workflows for {% data variables.product.prodname_actions %} are in private beta and are not available for new signups. On October 18th, 2023, you will no longer be able to access required workflows for {% data variables.product.prodname_actions %} and must use repository rulesets instead. You can read more about this change on the [{% data variables.product.company_short %} blog](https://github.blog/changelog/2023-08-02-github-actions-required-workflows-will-move-to-repository-rules/).{% ifversion fpt or ghec %} For more information about repository rulesets, see "[AUTOTITLE](/repositories/configuring-branches-and-merges-in-your-repository/managing-rulesets/about-rulesets)."{% endif %}
 
 {% endnote %}