ci: add design complete automation

[geospatialem]

Related Issue: n/a

Summary

Adds automation for our design complete process, where when the design-complete label is added the following occurs:

• Remove the design and 1 - assigned labels
  • Achieved through two separate removeLabel API calls, as there is not an API call to remove more than one without removing all labels.
• Add the 0 - new and needs milestone labels
• Clear the assignee(s) and milestone
• CC @brittneytewks and I in the issue's body
  • Achieved via the CALCITE_MANAGERS secret (current value: geospatialem, brittneytewks)

Leverages the ADMIN_TOKEN secret 🔒 for admin access to update the labels with the proper permissions. Updated to our default PAT using write permissions

[jcfranco]

⚡🤖⚡

[jcfranco]

The API calls are pretty expressive, so one suggestion to remove some comments with duplicate info is to use an object for common props and spread into each call:

const commonProps = { 
  issue_number: context.issue.number,
  owner: context.repo.owner,
  repo: context.repo.repo
};

await github.rest.issues.removeLabel({
  name: "design",
  ...commonProps
});

await github.rest.issues.removeLabel({
  name: "1 - assigned",
  ...commonProps
});