Add coment to explain NaN verify

[AlecsFarias]

Add comment to explain NaN verify

Just a comment to explain that this line is a NaN check. This type of verification can be a little confusing at first glance.

Description

^^

Checklist:

• All tests are passing
• Type definitions, if updated, pass both test-ts-defs and test-ts-usage
• Benchmark performance has not significantly decreased
• Bundle size has not been significantly impacted
• The bundle size badge has been updated to reflect the new size

[changeset-bot]

⚠️ No Changeset found

Latest commit: 0568785

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[carbonrobot]

Blocking for now. We should add this into another code change so we are not releasing a comment as a new version.

[ryan-roemer]

@carbonrobot -- the other thing to keep in mind is that this section is part of the explicitly copied-and-pasted from fast-deep-equal. We may want to long term consider a rewrite to not follow that model...