Incompatible with actions/checkout@v6 (original) (raw)

GitHub Actions published a new v6.0.0 version of actions/checkout. As soon as renovate pulled in this update, the create-pull-request action began to fail with the following output:

Checking the base repository state
  /usr/bin/git symbolic-ref HEAD --short
  <my branch name>
  Working base is branch '<my branch name>'
  /usr/bin/git remote prune origin
  remote: Duplicate header: "Authorization"
  fatal: unable to access '<repository URL': The requested URL returned error: 400
  Error: The process '/usr/bin/git' failed with exit code 128

The action configuration is pretty vanilla:

Rolling back to actions/checkout@v5 resolved the error and this action then runs as expected.