It was merged to master but not the stable-2.9 branch. Currently it's 382 commits behind master: https://github.com/tootsuite/mastodon/tree/stable-2.9/app
I ran into an issue generating the Elasticsearch indices, but I found a PR that was merged into master that's not part of Mastodon 2.9.3 that fixes it: https://github.com/tootsuite/mastodon/pull/11192.
The node name is set automatically from the server's hostname so that is not needed. The default cluster name is elasticsearch, do you have a suggestion for a name?
In my experience chef-run is far from ready: error messages are cryptic, I can't find a way to set a policy group (replaces environments) or to load data bag items, which is a deal breaker
I added a comment about the attributes in my review, the rest looks good!