Bump WooCommerce Admin version to 2.8.0

[Konamiman]

All Submissions:

• Have you followed the WooCommerce Contributing guideline?
• Does your code follow the WordPress' coding standards?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes proposed in this Pull Request:

This is the same pull request as #31071, which targeted the release/5.9 branch, but this time targeting trunk. See the original pull request for the changelog.

FOR PR REVIEWER ONLY:

• I have reviewed that everything is sanitized/escaped appropriately for any SQL or XSS injection possibilities. I made sure Linting is not ignored or disabled.

[github-actions]

Hi @barryhughes, thanks for merging this pull request. Please take a look at these follow-up tasks you may need to perform:

• Add the status: needs changelog label 🙅🏽
• Add the status: needs testing instructions label 🙅🏽