Arrays and Loops lesson: Fix incorrect link

[o1Suleyman]

This PR

• Replace https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Building_blocks/Looping_code#why_bother with corrected https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Building_blocks/Looping_code#why_are_loops_useful

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• I have thoroughly read and understand The Odin Project curriculum contributing guide
• The title of this PR follows the location of change: brief description of change format, e.g. Intro to HTML and CSS lesson: Fix link text
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