fix: use correct commiter avatars

[krzysdz]

User data from commits has different details than from activity. Commit data has much less information about authors and some of it is stored under different keys.

The only values that matter are:

• login: same in both
• avatar URL: avatar_url for ACTIVITY, avatarUrl for COMMIT
• activity count: added by the script, always as activityCount

Which type of data is used for an account, depends on the type of the first event with that account. Within a project "ACTIVITY" is processed before "COMMIT", but the project order matters and some people may have only "COMMIT" activity, so differences are expected unless profile data is fetched separately for COMMIT-only accounts. Example data:

// from ACTIVITY
{
    "login": "bjohansebas",
    "id": 103585995,
    "node_id": "U_kgDOBiyYyw",
    "avatar_url": "https://avatars.githubusercontent.com/u/103585995?v=4",
    "gravatar_id": "",
    "url": "https://api.github.com/users/bjohansebas",
    "html_url": "https://github.com/bjohansebas",
    "followers_url": "https://api.github.com/users/bjohansebas/followers",
    "following_url": "https://api.github.com/users/bjohansebas/following{/other_user}",
    "gists_url": "https://api.github.com/users/bjohansebas/gists{/gist_id}",
    "starred_url": "https://api.github.com/users/bjohansebas/starred{/owner}{/repo}",
    "subscriptions_url": "https://api.github.com/users/bjohansebas/subscriptions",
    "organizations_url": "https://api.github.com/users/bjohansebas/orgs",
    "repos_url": "https://api.github.com/users/bjohansebas/repos",
    "events_url": "https://api.github.com/users/bjohansebas/events{/privacy}",
    "received_events_url": "https://api.github.com/users/bjohansebas/received_events",
    "type": "User",
    "user_view_type": "public",
    "site_admin": false,
    "activityCount": 114
}
// from COMMIT
{
    "login": "wesleytodd",
    "id": "MDQ6VXNlcjEwMjc3NzY=",
    "avatarUrl": "https://avatars.githubusercontent.com/u/1027776?v=4",
    "url": "https://github.com/wesleytodd",
    "isSiteAdmin": false,
    "activityCount": 1
}