CopyButton returns undefined when copying workflow code on publish page

[katayama8000]

Description

On the package publish instructions page, clicking the copy button for the GitHub Actions workflow code results in undefined being copied to the clipboard instead of the actual YAML code.

Steps to Reproduce

1. Navigate to a package's publish page (e.g., /@scope/package/publish)
2. Scroll to the "Publish from CI" section
3. Click the copy button (📋) next to the workflow code block
4. Paste the clipboard contents
5. Expected: Clean YAML workflow code
6. Actual: undefined

[rgbkrk]

Same thing happens for the copy button after inviting a user to an org