security: add strict v3 CLA workflow

Signed-off-by: lawrencecchen <54008264+lawrencecchen@users.noreply.github.com>

Author: lawrencecchen

.github/CODEOWNERS

@@ -1 +1,9 @@
 * @lawrencecchen
+
+# CLA policy, its legal document, and the protected signature ledger require
+# review from both designated security maintainers.
+/.github/CODEOWNERS @austinywang @azooz2003-bit
+/.github/workflows/cla.yml @austinywang @azooz2003-bit
+/.github/scripts/ @austinywang @azooz2003-bit
+/CLA.md @austinywang @azooz2003-bit
+/signatures/ @austinywang @azooz2003-bit