Add "Standardizing CI/CD" workshop to the CI adoption landing zone

Why is this change being made?

I've put together a workshop that discusses benefits and strategies for setting up a standardized library of CI/CD components; these ideas have been very helpful for customers looking to consolidate on GitLab from other tools, but also to provide standard components to reduce security and compliance risks.

• The Highspot content still needs to be approved, and maybe moved to the right location if I got that wrong.
• The adoption landing zone page will need an internal link to the Highspot content.
• The adoption landing zone page will need a customer-facing link to the slides on Highspot once approved.
• I have recorded a sample video of myself presenting this workshop, but I'm not sure yet where that would be best shared.

Author Checklist

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