Support YAML Anchors

Problem

Note to incoming readers (2025) I will update this if anything changes, you don't need to read this entire thread. Update August 2025 Support has been added Update March 2025 @salilsub, a GitHub Staff member, has said that this is coming in the latter half of 2025!! Update Jan 2025 @salilsub started a Poll Comment to request interest in one of three proposed solutions. >🎉 : I need YAML anchors per the YAML spec 🚀 : I need a way to write YAML once and re-use it. I don't need YAML anchors specifically, but I need to have a way to do this in the same file as my workflow 👀 : I need a way to write YAML once and re-use it in my workflows. I can use either the same file or a different file I import. I really need templating (like the kind available in Azure DevOps Pipelines) A deadline for the poll has been set for the end of February. Personally, I think this poll is an inappropriate response this this issue. Update Aug 2024 This comment from staff says they will be looking at this next year > Thanks for engaging on this all, this is on our list to get to in the early part of next year. Right now we are re-working the services in Actions which do our YAML expansion (focusing on how we improve their availability). Once we are live with the new services we will start looking at adding features and this is on our list <3 How Can I Help? If you want to help, upvote this comment by reacting to it with 👍. This will help it sort higher in the issues list. Adding "me too"