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

[ujjwalv01]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• Migrates the tests in @stdlib/math/base/special/truncn from relative tolerance testing to ULP-based difference testing, utilizing @stdlib/assert/is-almost-same-value.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352

Questions

Any questions for reviewers of this pull request?

No.

Other

Any other information relevant to this pull request? This may include screenshots, references, and/or implementation notes.

The isAlmostSameValue function replaces the manual delta <= tol checks with a ULP budget of 1.

Checklist

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

• Read, understood, and followed the contributing guidelines.

AI Assistance

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• Yes
• No

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• Code generation (e.g., when writing an implementation or fixing a bug)
• Test/benchmark generation
• Documentation (including examples)
• Research and understanding

Disclosure

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@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
math/base/special/truncn	$\\color{green}268/268$ $\\color{green}+100.00\\%$	$\\color{green}23/23$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}268/268$ $\\color{green}+100.00\\%$

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

[kgryte]

LGTM