Add numpy.ndarray.all() method documentation (#7869)

[ylevental]

Description

This PR adds comprehensive documentation for the all() method under NumPy ndarray. The entry includes:

• Detailed description of the method and its use cases
• Complete syntax section with all parameters explained
• Four detailed examples demonstrating different use cases (basic validation, axis-wise operations, keepdims usage, and where parameter)
• Interactive codebyte example for practical validation scenarios

Issue Solved

Closes #7869

Type of Change

• Adding a new entry

Checklist

• All writings are my own.
• My entry follows the Codecademy Docs style guide.
• My changes generate no new warnings.
• I have performed a self-review of my own writing and code.
• I have checked my entry and corrected any misspellings.
• I have made corresponding changes to the documentation if needed.
• I have confirmed my changes are not being pushed from my forked main branch.
• I have confirmed that I'm pushing from a new branch named after the changes I'm making.
• I have linked any issues that are relevant to this PR in the Issues Solved section.

[mamtawardhani]

Looks good for a second review! 🚀

[Sriparno08]

Looks good, @ylevental!

[github-actions]

👋 @ylevental
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