Add syntax highlighting to atl-mfc-shared

[HO-COOH]

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[opbld33]

Docs Build status updates of commit 8f6a4e7:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/atl-mfc-shared/reference/cfixedstringt-class.md	✅Succeeded
docs/atl-mfc-shared/reference/cimage-class.md	✅Succeeded
docs/atl-mfc-shared/reference/coledatetime-class.md	✅Succeeded
docs/atl-mfc-shared/reference/coledatetimespan-class.md	✅Succeeded
docs/atl-mfc-shared/reference/cpoint-class.md	✅Succeeded
docs/atl-mfc-shared/reference/crect-class.md	✅Succeeded
docs/atl-mfc-shared/reference/csize-class.md	✅Succeeded
docs/atl-mfc-shared/reference/cstrbuft-class.md	✅Succeeded
docs/atl-mfc-shared/reference/cstringdata-class.md	✅Succeeded
docs/atl-mfc-shared/reference/ctime-class.md	✅Succeeded
docs/atl-mfc-shared/reference/ctimespan-class.md	✅Succeeded
docs/atl-mfc-shared/reference/iatlstringmgr-class.md	✅Succeeded

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Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

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PRMerger Results

Issue	Description
Changed Files	This PR contains more than 10 changed files.

[Jak-MS]

@TylerMSFT

• Can you review this PR?
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#label:"aq-pr-triaged"
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[TylerMSFT]

Thank you @HO-COOH! Appreciate you taking the time to do this.

[TylerMSFT]

#sign-off