Fix cargo clippy warnings in PR #138

[dmidem]

This PR addresses a couple of cargo clippy warnings in PR #138.

[what-the-diff]

PR Summary

• Introduction of a new asset_record module

  • A new structural model representation for collective asset data, named AssetRecord, has been introduced. This includes characteristics such as the amount of the asset, its completion status, and a reference note.
  • This module also includes ways to create AssetRecord.

• Removal of supply_info module

  • The former module supply_info and its functions has been removed completely.

• Updates to lib.rs

  • This update implements the previously added asset_record module and removes the now irrelevant supply_info module.

• Tests added to issuance_global_state.rs

  • To ensure the issuance process workflow is correct, tests have been added. This is to specifically validate the bundling process in terms of global state, both with and without error.

• Changes to assertions in zsa.rs

  • Verification calls in the issue_zsa_notes function now employ a closure that yields None replacing a HashSet.

[dmidem]

Closed in favour of #140.