test: migrate math/base/special/cbrtf to ULP-based testing

[ujjwalv01]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• Migrates the @stdlib/math/base/special/cbrtf package tests from relative tolerance testing to ULP-based difference testing using isAlmostSameValue.
• Removes all outdated delta and tol variables across the package test files.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• None

Questions

Any questions for reviewers of this pull request?

No.

Other

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No.

Checklist

Please ensure the following tasks are completed before submitting this pull request.

• Read, understood, and followed the contributing guidelines.

AI Assistance

When authoring the changes proposed in this PR, did you use any kind of AI assistance?

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• No

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• Code generation (e.g., when writing an implementation or fixing a bug)
• Test/benchmark generation
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@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
math/base/special/cbrtf	$\\color{green}180/180$ $\\color{green}+0.00\\%$	$\\color{green}5/5$ $\\color{green}+0.00\\%$	$\\color{green}2/2$ $\\color{green}+0.00\\%$	$\\color{green}180/180$ $\\color{green}+0.00\\%$

The above coverage report was generated for the changes in this PR.

[kgryte]

LGTM