feat: add C implementation for blas/ext/base/ndarray/ssumkbn

[Siddhram]

Description

What is the purpose of this pull request?

This pull request:

• feat: add C implementation for blas/ext/base/ndarray/ssumkbn

Related Issues

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This pull request has the following related issues:

• No.

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Other

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• Read, understood, and followed the contributing guidelines.

AI Assistance

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• Test/benchmark generation
• Documentation (including examples)
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@stdlib-js/reviewers

[MeKaustubh07]

LGTM, On to the @kgryte.

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
blas/ext/base/ndarray/ssumkbn	$\\color{green}176/176$ $\\color{green}+100.00\\%$	$\\color{green}7/7$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}176/176$ $\\color{green}+100.00\\%$

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

[MeKaustubh07]

@Siddhram you need to add <!-- /.examples --> tag.