Unused assignment with test_event

[QiLOL]

Description

The following warning was raised when the account module was involved:

1538 │         let eventhandle = &borrow_global<Account>(addr).coin_register_events;
     │             ^^^^^^^^^^^ Unused assignment or binding for local 'eventhandle'. Consider removing, replacing with '_', or prefixing with '_' (e.g., '_eventhandle')

How Has This Been Tested?

aptos move test

Key Areas to Review

Simply avoid warning.

Type of Change

• New feature
• Bug fix
• Breaking change
• Performance improvement
• Refactoring
• Dependency update
• Documentation update
• Tests

Which Components or Systems Does This Change Impact?

• Validator Node
• Full Node (API, Indexer, etc.)
• Move/Aptos Virtual Machine
• Aptos Framework
• Aptos CLI/SDK
• Developer Infrastructure
• Move Compiler
• Other (specify)

Checklist

• I have read and followed the CONTRIBUTING doc
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I identified and added all stakeholders and component owners affected by this change as reviewers
• I tested both happy and unhappy path of the functionality
• I have made corresponding changes to the documentation

[trunk-io]

⏱️ 4s total CI duration on this PR

Job	Cumulative Duration	Recent Runs
permission-check	2s	🟥
permission-check	2s	🟥

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