Add REST API to return group's shared groups

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What does this MR do and why?

Add API to return group's shared groups

• REST API endpoint GET /groups/:id/groups/shared to Get a list of shared groups this group was invited to

• Added new rate limitation group_shared_groups_api_limit

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/groups/:id/groups/shared	60 requests per minute

Closes #424959 (closed)

DB review

• https://console.postgres.ai/shared/8f664673-2c7e-4d5a-9f9b-93937a8f85ec default sort
• https://console.postgres.ai/shared/870d1410-02ab-4ea9-91b1-34e8cf1f6d32 sort by similarity
• https://console.postgres.ai/shared/7c80c399-8f37-4a09-ae9c-55082cde2d3b with visibility filter

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