Update plan-defender-for-servers-agents.md

[baardhermansen]

Corrected the URL for on-premises machines, it was pointing to AWS.

[prmerger-automator[bot]]

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[opbld32]

Learn Build status updates of commit 86213e1:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
articles/defender-for-cloud/plan-defender-for-servers-agents.md	:white_check_mark:Succeeded

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[Jak-MS]

@bmansheim

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

[bmansheim]

Thanks for collaborating with us to make the docs great, @baardhermansen !

#sign-off