[WIKI]: Fix broken Pillow installation link in Troubleshooting wiki page

Describe the bug

The Troubleshooting Wiki page contains a broken reference for resolving Pillow/zlib installation errors.

Location: > Wiki Page: Troubleshooting
Section: Installation Issues (or macOS specific section)
Broken Link: https://github.com/python-pillow/Pillow/issues/3438

Proposed Fix:
Update the Wiki link to point to the official Pillow documentation: https://pillow.readthedocs.io/en/stable/installation.html#building-from-source

I would like to be assigned this to update the Wiki.

URL of the page where the issue is observed.

https://github.com/oppia/oppia/wiki/Troubleshooting

Steps To Reproduce

Navigate to the Oppia GitHub home page.

On the top bar of sections, navigate to Wiki.

Scroll down to the "MacOS" section or click on the link at the top of the page Command cc failed with exit status 1

Locate and click the link under the reference: https://github.com/python-pillow/Pillow/issues/3438.

Observe that GitHub displays a "404 Not Found" page.

Expected Behavior

Expected Behaviour:
The link on the Troubleshooting wiki page should direct the user to a valid, official resource for resolving Pillow and zlib installation dependencies. This ensures that new developers, particularly those on macOS, can successfully complete their local environment setup without encountering broken documentation.

Screenshots/Videos

No response

What device are you using?

Desktop

Operating System

MacOS

What browsers are you seeing the problem on?

Safari

Browser version

No response

Additional context

No response

Tips for developers

Before addressing the bug, please identify which PR caused the issue (you can follow the steps here). If you identify the PR, comment on the issue with a link to it. If not, mention the commit hash of the oldest commit you saw the bug on (and the month and year it was made in).

Then, please leave a comment with details of the approach that you plan to take to fix the issue (see example).

Note: If this is your first Oppia issue, please make sure to follow our guidelines for choosing an issue and setting things up. You will also need to show a demo of the fix working correctly on your local machine. Thanks!

Open the Troubleshooting Wiki page and locate the Installation Issues or macOS section, especially the “Command cc failed with exit status 1” entry. Replace the broken Pillow issue link with the official Pillow installation documentation URL provided in the issue. Done means the wiki link opens successfully and points to the building-from-source guidance.