created cred scan page

Author: ElazarK

articles/defender-for-cloud/TOC.yml

@@ -562,6 +562,9 @@
     - name: Defender for DevOps FAQ
       displayName: DevOps, FAQ
       href: devops-faq.md
+    - name: Credential scanner rules
+      displayName: credential, scanner, rules, DevOps
+      href: concept-credential-scanner-rules.md
 
 - name: Reference
   items: