Restore GitLab Flow redirect for a year

What does this MR do?

As requested in !127638 (comment 2148037245), restores the GitLab Flow redirect for another year. This MR copies the contents of !139967 (merged) and changes the dates.

FYI - @brendan777, we should chat about the history of this page, as it was a little bit Source Code and a little bit Code Review.

Related issues

• Related to https://gitlab.com/gitlab-org/gitlab/-/issues/463610+
• Related to Restore external gitlab-flow redirect removed t... (!139967 - merged)
• Related to https://gitlab.com/gitlab-com/customer-success/professional-services-group/education-services/-/issues/730+ where the PREVIOUS too-soon redirect removal was found
• Related to Redact GitLab Flow page, create a redirect (!127638 - merged) where the PREVIOUS redirect was merged with a 3-month limit
• Related to Gitlab Flow Docs - Adding Enablement Content fo... (#378297 - closed) which tracks the full arc of problems with this page over the years
• Related to Blog Post - The GitLab Flow with GitLab Duo: a ... (gitlab-com/www-gitlab-com!127409 - merged) where the blog post was published
• Related to https://gitlab.com/gitlab-org/gitlab/-/issues/357415+

Author's checklist

• Optional. Consider taking the GitLab Technical Writing Fundamentals course.
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Reviewer's checklist

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