## Description 

Put tests in sui-types/object.rs in their own module
The tests are just floating around in the main module, which presumably
means they are also compiled into our production builds? They should go
into their own module, guarded by a #[cfg(test] annotation.

## Test plan 

How did you test the new or updated feature?

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## Release notes

Check each box that your changes affect. If none of the boxes relate to
your changes, release notes aren't required.

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that describes the impact of your changes that a user might notice and
any actions they must take to implement updates.

- [ ] Protocol: 
- [ ] Nodes (Validators and Full nodes): 
- [ ] Indexer: 
- [ ] JSON-RPC: 
- [ ] GraphQL: 
- [ ] CLI: 
- [ ] Rust SDK:
- [ ] REST API: