Revert "Add callback to getSetting to support async jsonata access"

packages/node_modules/@node-red/runtime/lib/flows/index.js

@@ -780,7 +780,7 @@ const flowAPI = {
     getNode: getNode,
     handleError: () => false,
     handleStatus: () => false,
-    getSetting: (k, callback) => flowUtil.getEnvVar(k, callback),
+    getSetting: k => flowUtil.getEnvVar(k),
     log: m => log.log(m)
 }