Markdown heading level bug in Narrowing documentation

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Comment

URL: https://www.typescriptlang.org/docs/handbook/2/narrowing.html#truthiness-narrowing

Issue: In the "Narrowing" handbook page, the heading for "Truthiness narrowing" is written as an H1 (# Truthiness narrowing) instead of an H2 (## Truthiness narrowing).

Because of this markdown typo, all the subsequent parallel narrowing concepts (Equality narrowing, The in operator narrowing, instanceof narrowing, etc.) are incorrectly nested under "Truthiness narrowing" in the Table of Contents, which might confuse readers into thinking they are sub-concepts of Truthiness narrowing.