Lock asset feature

[JahnabDutta]

Proposed Changes

• Add locking mechanism for assets by creating an in memory record of the occupied status of the asset.
• Create two new types of action types in the /operate_assets, namely lock_asset and unlock_asset.
• Validate all actions to the /operate_assets api based on the lock.

Associated Issue

• related to User Notification for Concurrent Viewers under Live Camera Feed Enhancement

Merge Checklist

• [ ] Tests added/fixed
• [ ] Update docs in /docs
• [ ] Linting Complete
• [ ] Any other necessary step

Only PR's with test cases included and passing lint and test pipelines will be reviewed

@coronasafe/care-backend-maintainers @coronasafe/care-backend-admins