Add Integration Tests for User Sharing API

[BimsaraBodaragama]

This PR introduces comprehensive integration tests for the User Sharing API, ensuring correctness in user sharing, unsharing, and verification through a successful GET request for a user's shared organizations and assigned shared roles to a shared user in a given organization. These tests validate request handling, response accuracy, and expected behavior across various valid and invalid scenarios, ensuring API reliability in standard usage.

Test Coverage:

✅ Successful Scenarios

1. Selective User Sharing:
   • Covers single and multiple users across multiple organizations.
   • Validates all selective resource-sharing policies:
     • SELECTED_ORG_ONLY
     • SELECTED_ORG_WITH_ALL_EXISTING_CHILDREN_ONLY
     • SELECTED_ORG_WITH_ALL_EXISTING_AND_FUTURE_CHILDREN
     • SELECTED_ORG_WITH_EXISTING_IMMEDIATE_CHILDREN_ONLY
     • SELECTED_ORG_WITH_EXISTING_IMMEDIATE_AND_FUTURE_CHILDREN
2. General User Sharing:
   • Covers single and multiple users.
   • Validates all general resource-sharing policies:
     • ALL_EXISTING_ORGS_ONLY
     • ALL_EXISTING_AND_FUTURE_ORGS
     • IMMEDIATE_EXISTING_ORGS_ONLY
     • IMMEDIATE_EXISTING_AND_FUTURE_ORGS
3. General User Unsharing:
   • Covers single and multiple users.
4. Selective User Unsharing:
   • Covers single and multiple users.
   • Covers single and multiple organizations.

❌ Failure Scenarios

1. Selective User Sharing:
   • Selective User Sharing with invalid roles (single and multiple invalid roles).
   • Selective User Sharing with invalid organizations (single and multiple invalid organizations).
   • Selective User Sharing with invalid users (single and multiple invalid users).
   • Selective User Sharing with conflicting users (user exists in a child organization under the same username).
   • Selective User Sharing with non-immediate child organizations.
2. General User Sharing:
   • General User Sharing with invalid roles.
   • General User Sharing with invalid users.
   • General User Sharing with conflicting users.
3. General User Unsharing:
   • General User Unsharing with invalid users (single and multiple invalid users).
4. Selective User Unsharing:
   • Selective User Unsharing with invalid users and invalid organizations (single and multiple cases).
5. Selective User Re-Sharing:
   • Invalid Selective User Re-sharing (a shared user from a parent org cannot be re-shared from a child org).
6. General User Re-Sharing:
   • Invalid General User Re-sharing (a shared user from a parent org cannot be re-shared from a child org).

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Related Issue

Add Integration Tests for User Sharing API #23328

[BimsaraBodaragama]

Integration Test Runner

Attempt 1

Integration Test Runner For this PR can be found here.
Status: Successful ✅

Attempt 2

Integration Test Runner For this PR can be found here.
Status: Successful ✅

Attempt 3

Integration Test Runner For this PR can be found here.
Status: Successful ✅

Attempt 4

Integration Test Runner For this PR can be found here.
Status: Successful ✅

Attempt 5

Integration Test Runner For this PR can be found here.
Status: Successful ✅

The integration test runner for this PR has been triggered and executed multiple times to ensure there are no intermittent test failures caused by awaiting the completion of asynchronous processes involved in these integration tests introduced in this PR.

[AnuradhaSK]

Please squash the commits

[BimsaraBodaragama]

The changes originally intended in this PR will now be tracked in a different PR: #23423