Add the cred scan step (Azure#18505)

Author: sima-zhu

eng/CredScanSuppression.json

@@ -0,0 +1,4 @@
+{
+    "tool": "Credential Scanner",
+    "suppressions": []
+}

eng/common/pipelines/templates/steps/verify-links.yml

@@ -26,4 +26,4 @@ steps:
         -branchReplaceRegex "${{ parameters.BranchReplaceRegex }}"
         -branchReplacementName ${{ parameters.BranchReplacementName }}
         -devOpsLogging: $true
-        -checkLinkGuidance: ${{ parameters.CheckLinkGuidance }}
+        -checkLinkGuidance: ${{ parameters.CheckLinkGuidance }}