[AzureADDS] TOC update for doc retired in MicrosoftDocs/azure-docs-pr#109762

Author: iainfoulds

articles/active-directory-domain-services/TOC.yml

@@ -151,7 +151,5 @@
       href: https://azure.microsoft.com/pricing/details/active-directory-ds/
     - name: Azure AD feedback forum
       href: https://feedback.azure.com/forums/169401-azure-active-directory
-    - name: Contact us
-      href: contact-us.md
     - name: Use Azure AD Domain Services in Azure CSP subscriptions
       href: csp.md