Refactoring to avoid race condition and resolve CodeQL returnless function alert 56

[ajb176]

Fixes #5473

What changes did you make?

• Replaced a returnless function with an anonymous function to avoid CodeQL alert 56
• Added an if conditional to set up an event listener only if the document is still in the loading state
• Added an else clause to run InsertEventSchedule if the document is not in the loading state

Why did you make the changes (we will use this info to test)?

• Because the original function passed to the addEventListener contained parameters, the function was called immediately and the event listener expected its parameter to be that function's return value. Using an anonymous function (without parameters) to then call the InsertEventSchedule ensured the event listener only fired the function once the necessary event occured.
• The previous code was only functional because the event listener was set up incorrectly, otherwise the event listener would have missed the DOMContentLoaded event and never run its callback function. This made it necessary to re-format the script to load the event schedule without the race condition of the DOM content.
• If the document readyState is still loading, the event listener can be added to wait for the DOMContentLoaded event before populating the event schedule. If the readyState is past the loading state ('interactive'), the DOM content has already loaded and the event schedule can be populated.

Video of Proposed Changes to The Website

Visuals before changes are applied

beforechangescodeql.mov

Visuals after changes are applied

codeqlshortafterchange.mov

[github-actions]

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From your project repository, check out a new branch and test the changes.

git checkout -b ajb176-fix-returnless-5473 gh-pages
git pull https://github.com/ajb176/website.git fix-returnless-5473

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[W1LD-R]

Hi @ajb176 — nicely done!

• I like your solution, it's concise and it works as expected when I view the site on your branch
• Your branch is correct
• You linked the issue correctly in your PR description
• You clearly described the changes, stated the reason for making them, and provided before/after gifs
• Everything looks good across mobile and desktop on Chrome and Firefox

Approved! 👍

[aqandrew]

This works exactly as expected, and your explanation is very sound! Great job.

Also, thank you for sharing your approach for the same problem in #6536.