added str-repeat.md in str-repeat folder in the string functions in php

[MMMMMMMZ]

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[CLAassistant]

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[SSwiniarski]

@MMMMMMMZ I did a first review and left a few comments.

[SSwiniarski]

@MMMMMMMZ Aside from one extra space, looks good for a second review.

[MMMMMMMZ]

@SSwiniarski ok, is it ready now for the second review?

[KTom101]

@MMMMMMMZ I've added a second review.

[SSwiniarski]

@MMMMMMMZ I did a fix to the filename (it was missing the ".md") and ran an npm format so the linting checks would pass. This should be ready to merge once @KTom101 reviews again and approves your edits.

[KTom101]

@MMMMMMMZ Looks good 👍

[github-actions]

👋 @MMMMMMMZ
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[KTom101]

@MMMMMMMZ Live link is here: https://www.codecademy.com/resources/docs/php/string-functions/str-repeat

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cc @yangc95 @SSwiniarski