test(redis-cloud): comprehensive test coverage for account, ACL, and cloud accounts handlers

[joshrotenberg]

Summary

• Enhanced test coverage for account, ACL, and cloud accounts handlers in the redis-cloud crate
• Added 57 comprehensive tests that follow the OpenAPI spec exactly
• All tests pass successfully

Test Coverage Details

Account Handler (17 tests)

• ✅ All 8 methods covered
• ✅ Edge cases: Optional parameters, empty responses, different providers
• ✅ Error handling: 401, 404, 500 HTTP errors
• ✅ Forward compatibility with extra fields

ACL Handler (22 tests)

• ✅ All 11 methods covered
• ✅ Complex request structures with roles, rules, and users
• ✅ Task state handling for async operations
• ✅ Comprehensive error handling

Cloud Accounts Handler (18 tests)

• ✅ All 5 methods covered
• ✅ Multi-cloud support: AWS, GCP, Azure
• ✅ Request variations and response scenarios
• ✅ Error handling including 403 forbidden

Test Results

Running tests/account_tests.rs: 17 passed
Running tests/acl_tests.rs: 22 passed  
Running tests/cloud_accounts_tests.rs: 18 passed

All 57 tests pass successfully.