Added file on chisquare_test

[Neema-Joju]

Description

Added a new file entry on chi-square test. Improving documentation and providing more context for the users to understand.

Issue Solved

#5689

Type of Change

• Adding a new entry
• Updating the documentation

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]

Thank you for contributing to Codecademy Docs @Neema-Joju 😄

The entry looks good for a second round of review! 🚀

[Neema-Joju]

Hi @mamtawardhani
I was going through the changes made. I would like to point out a small error. The chi square test in statsmodel cannot be applied to check goodness-of-fit and test of independence. It can only be used to check if the proportions are different from the expected. I think scipy chi-square test can check goodness of fit but not the other way around.