docs: improve doctests for ndarray instances in ndarray/includes

[ShreelaxmiHegde]

Progresses #9329.

Description

What is the purpose of this pull request?

This pull request:

• Updates the examples for ndarray/includes package, by migrating to using ndarray instance notation.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: Improve doctests for ndarray instances in documentation examples (tracking issue) #9329

Questions

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No.

Other

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No.

Checklist

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• Read, understood, and followed the contributing guidelines.

AI Assistance

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• No

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Coverage Report

Package	Statements	Branches	Functions	Lines
ndarray/includes	$\color{red}356/508$ $\color{green}+70.08%$	$\color{green}4/4$ $\color{green}+100.00%$	$\color{red}0/3$ $\color{green}+0.00%$	$\color{red}356/508$ $\color{green}+70.08%$

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