Add Copilot to the CLA allow list

[juliasilge]

Addresses #987 to try once more to get this working

The GitHub API says that user is:

{                                                                                
       "login": "Copilot",
       "id": 198982749,
       "node_id": "BOT_kgDOC9w8XQ",
       "avatar_url": "https://avatars.githubusercontent.com/in/1143301?v=4",
       "gravatar_id": "",
       "url": "https://api.github.com/users/Copilot",
       "html_url": "https://github.com/apps/copilot-swe-agent",
       "followers_url": "https://api.github.com/users/Copilot/followers",
       "following_url": "https://api.github.com/users/Copilot/following{/other_user}",
       "gists_url": "https://api.github.com/users/Copilot/gists{/gist_id}",
       "starred_url": "https://api.github.com/users/Copilot/starred{/owner}{/repo}",
       "subscriptions_url": "https://api.github.com/users/Copilot/subscriptions",
       "organizations_url": "https://api.github.com/users/Copilot/orgs",
       "repos_url": "https://api.github.com/users/Copilot/repos",
       "events_url": "https://api.github.com/users/Copilot/events{/privacy}",
       "received_events_url": "https://api.github.com/users/Copilot/received_events",
       "type": "Bot",
       "user_view_type": "public",
       "site_admin": false,
       "name": null,
       "company": null,
       "blog": "",
       "location": null,
       "email": null,
       "hireable": null,
       "bio": null,
       "twitter_username": null,
       "public_repos": 0,
       "public_gists": 0,
       "followers": 0,
       "following": 0,
       "created_at": "2025-02-12T20:26:08Z",
       "updated_at": "2025-02-13T21:14:06Z"
     }