Add changeset version

Author: s0

.changeset/green-dogs-change.md

@@ -0,0 +1,10 @@
+---
+"@changesets/action": major
+---
+
+Start using GitHub API to push tags and commits to repos
+
+Rather than use local git commands to push changes to GitHub,
+this action now uses the GitHub API directly,
+which means that all tags and commits will be attributed to the user whose
+GITHUB_TOKEN is used, and signed.