Remove Defender for Cloud integration section and articles

- Removed Defender for Cloud integration section from TOC.yml
- Deleted defender-for-cloud-defender-portal.md
- Deleted cloud-scopes-unified-rbac.md
- Deleted cloud-asset-inventory.md
- Removed media/defender-for-cloud-defender-portal/ directory and all images
- Fixed broken references in work-attack-paths-overview.md, whats-new.md, vulnerability-management-integration.md, and security-recommendations.md

Author: DebLanger

exposure-management/TOC.yml

@@ -72,14 +72,6 @@
       items:
         - name: Vulnerability management integration with Exposure Management
           href: vulnerability-management-integration.md
-    - name: Defender for Cloud integration
-      items:
-        - name: Defender for Cloud in the Defender portal
-          href: defender-for-cloud-defender-portal.md
-        - name: Cloud scopes and Unified RBAC
-          href: cloud-scopes-unified-rbac.md
-        - name: Cloud asset inventory
-          href: cloud-asset-inventory.md
     - name: Manage exposure with security insights
       items:
         - name: Overview