bench: generate arrays with NaN values

[ujjwalv01]

Description

What is the purpose of this pull request?

This pull request:

• Updates the benchmark.native.js implementations for @stdlib/stats/base/ndarray/dnanmean, dnanmeanors, and dnanmeanwd.
• Ensures the native benchmarks correctly track their respective benchmark.js implementations by properly injecting NaN values into the test arrays using bernoulli and fillBy.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• Follow-up to previous reviews.

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?

• 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
stats/base/ndarray/dnanmean	$\\color{green}176/176$ $\\color{green}+100.00\\%$	$\\color{green}7/7$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}176/176$ $\\color{green}+100.00\\%$
stats/base/ndarray/dnanmeanors	$\\color{green}176/176$ $\\color{green}+100.00\\%$	$\\color{green}7/7$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}176/176$ $\\color{green}+100.00\\%$
stats/base/ndarray/dnanmeanwd	$\\color{green}176/176$ $\\color{green}+100.00\\%$	$\\color{green}7/7$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}176/176$ $\\color{green}+100.00\\%$

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

[kgryte]

LGTM. Thanks for the follow-up, @ujjwalv01!