Update manage-creation-of-groups.md

[SixPraxis]

Added -All switch to Get-MgBetaGroup cmdlet to ensure success in tenants with more groups than the default returned sample size.

[learn-build-service-prod]

Learn Build status updates of commit 22257cf:

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microsoft-365/solutions/manage-creation-of-groups.md	✅Succeeded

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[v-mathavale]

changes are implemented in private repo.