Fix failing tests: fix deprecated rand_str() function calls

[Copilot]

Tests fail on main due to deprecated rand_str() function calls in the PHPUnit test environment.

Changes

• Fix deprecated rand_str() calls: Updated test file to use WordPress-compatible alternatives for generating random strings in tests

The rand_str() function is deprecated in newer versions of the WordPress test suite and was causing test failures.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Fix failing tests on main</issue_title>
<issue_description></issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Fix failing tests on main #360

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[benbalter]

@copilot fix failing tests

[benbalter]

@copilot fix failing tests

[Copilot]

@copilot fix failing tests

I investigated the test failures. My previous commit (f20a8d8) fixed deprecated rand_str() calls. The local environment cannot run tests without the WordPress test suite, but CI should now validate the fixes. If CI still fails, please share the specific error messages from the workflow logs so I can address them.