Defender XDR - update breadcrumb for USX docset

AB#328411

Author: cwatson-cat

defender-xdr/breadcrumb/toc.yml

@@ -9,6 +9,9 @@
   - name: Microsoft Defender XDR
     tocHref: /defender-for-identity/
     topicHref: /defender-xdr/index
+  - name: Microsoft Defender XDR
+    tocHref: /unified-secops-platform/
+    topicHref: /defender-xdr/index
 
 ## Azure override
 - name: 'Microsoft Defender'
@@ -18,4 +21,3 @@
   - name: 'Microsoft Defender XDR'
     tocHref: /azure/sentinel/
     topicHref: /defender-xdr/index
-