Update Mastodon system dependencies

Needs new Ruby, and why not upgrade Yarn in the process. Running in
production.

nodes/andromeda.kosmos.org.json

@@ -108,7 +108,8 @@
       "kosmos-base::letsencrypt",
       "git::default",
       "git::package",
-      "build-essential::default"
+      "build-essential::default",
+      "poise-git::default"
     ],
     "platform": "ubuntu",
     "platform_version": "18.04",

site-cookbooks/kosmos-mastodon/recipes/default.rb

@@ -79,10 +79,10 @@ package %w(imagemagick ffmpeg libxml2-dev libxslt1-dev file git curl pkg-config
            libprotobuf-dev protobuf-compiler libidn11 libidn11-dev libjemalloc1)
 
 npm_package "yarn" do
-  version "1.17.3"
+  version "1.22.4"
 end
 
-ruby_version = "2.6.5"
+ruby_version = "2.6.6"
 
 execute "systemctl daemon-reload" do
   command "systemctl daemon-reload"