Add Contrast SAST Scan workflow child

Author: LiyangW

Diff for: .github/workflows/contrast-sast-scan-child.yml

@@ -0,0 +1,13 @@
+name: Contrast SAST Scan
+
+on:
+  push:
+    branches:
+      - master
+      - main
+  workflow_dispatch:
+
+jobs:
+  sast-scan:
+    uses: ibm-skills-network/.github/.github/workflows/contrast-sast-scan.yaml@main
+    secrets: inherit