feat: fixed broken link

[opensourcevk]

application insights link was broken, updated with correct one

[prmerger-automator[bot]]

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[learn-build-service-prod[bot]]

Learn Build status updates of commit 2ca5e11:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
articles/api-management/api-management-howto-app-insights.md	:white_check_mark:Succeeded

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[Jak-MS]

@dlepow

• Can you review this PR?
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#label:"aq-pr-triaged" @MicrosoftDocs/public-repo-pr-review-team

[opensourcevk]

@dlepow Can you review this PR?