Page of only Event Videos

[ckenst]

• I'd like to create a new page (not post) where we can dynamically load in the past.yml file and pull in only those conferences which have the video_url tag present.
• Then we will display a small subset of data such as Name of the Conference and the Url.

[ckenst]

This is being handled by #670.

A few things TODO:

• I want to separate out the list by year, e.g. 2023, 2022. If this works we can apply to past conferences list
• Need text introducing the page and the purpose. How to use it, etc.
• Figure out where to include it in the sub-navigation
• Move something out of the sub-navigation?