Add REST API invited groups in a project

What does this MR do and why?

Implement projects REST API to return the equivalent of https://gitlab.com/groups/project/\\\<full path\\\>/-/project_members?tab=groups.

• Invited groups in a project: /projects/:id/invited_groups
• Ensure API is rate limited
• Update docs
• Add query plans to the MR description

Note: If the request is unauthenticated and the endpoint could be accessed without authentication and not already rate-limited then the endpoint will be rate-limited by IP and it will have the same value as for the rate-limiting by the user.

Endpoint	Rate limit per user
GET /api/v4/projects/:id/invited_groups	60 requests per minute

Closes #465207 (closed)

Query Plans

• search: https://postgres.ai/console/gitlab/gitlab-production-main/sessions/30771/commands/95561
• min_access_level: https://postgres.ai/console/gitlab/gitlab-production-main/sessions/30771/commands/95562
• relation: https://postgres.ai/console/gitlab/gitlab-production-main/sessions/30771/commands/95563
• all relation: https://console.postgres.ai/gitlab/gitlab-production-main/sessions/30801/commands/95637

MR acceptance checklist

curl -X GET 'http://localhost:3000/api/v4/projects/19/invited_groups'

[
  {
    "id": 35,
    "web_url": "http://127.0.0.1:3000/groups/twitter",
    "name": "Twitter",
    "avatar_url": null,
    "full_name": "Twitter",
    "full_path": "twitter"
  },
  {
    "id": 33,
    "web_url": "http://127.0.0.1:3000/groups/flightjs",
    "name": "Flightjs",
    "avatar_url": null,
    "full_name": "Flightjs",
    "full_path": "flightjs"
  },
  {
    "id": 31,
    "web_url": "http://127.0.0.1:3000/groups/jashkenas",
    "name": "Jashkenas",
    "avatar_url": null,
    "full_name": "Jashkenas",
    "full_path": "jashkenas"
  },
  {
    "id": 24,
    "web_url": "http://127.0.0.1:3000/groups/gitlab-org",
    "name": "Gitlab Org",
    "avatar_url": null,
    "full_name": "Gitlab Org",
    "full_path": "gitlab-org"
  },
  {
    "id": 22,
    "web_url": "http://127.0.0.1:3000/groups/toolbox",
    "name": "Toolbox",
    "avatar_url": null,
    "full_name": "Toolbox",
    "full_path": "toolbox"
  }
]

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