Adds script to regulate staging deploys (#1979)

scripts/staging-deploy.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+
+echo "VERCEL_GIT_COMMIT_REF: $VERCEL_GIT_COMMIT_REF"
+
+if [[ "$VERCEL_GIT_COMMIT_REF" == "staging" ]] ; then
+  # Proceed with the build
+    echo "✅ - Build can proceed"
+    ./vercel.sh
+  exit 1;
+
+else
+  # Don't build
+  echo "🛑 - Build cancelled"
+  exit 0;
+fi