Download core/sync when testing

scripts/test.sh

@@ -292,6 +292,7 @@ case "$TARGET" in
   npm run check-environment
   download_server
   start_server
+  node ./scripts/download-realm.js ios --sync
   pushd tests/react-test-app
   npm install
   open_chrome
@@ -303,6 +304,7 @@ case "$TARGET" in
   ;;
 "react-example")
   npm run check-environment
+  node ./scripts/download-realm.js ios --sync
   pushd examples/ReactExample
 
   npm install