Remove unused function and its tests.

[dmjb]

In a previous PR, I removed all usages of a function except for one located in a test. I moved the function into the tests as a private function in response. I have since realized that the tests were testing this function. After deleting the tests, there are no other uses of this function, and it can be deleted.

Summary

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Fixes #(related issue)

Change Type

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• Bug fix (resolves an issue without affecting existing features)
• Feature (adds new functionality without breaking changes)
• Breaking change (may impact existing functionalities or require documentation updates)
• Documentation (updates or additions to documentation)
• Refactoring or test improvements (no bug fixes or new functionality)

Testing

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Review Checklist:

• Reviewed my own code for quality and clarity.
• Added comments to complex or tricky code sections.
• Updated any affected documentation.
• Included tests that validate the fix or feature.
• Checked that related changes are merged.

[coveralls]

coverage: 54.299%. remained the same
when pulling 8709064 on remove-redundant-tests
into c783987 on main.