Add nestedKey property to pino config (#41974)

types/pino/index.d.ts

@@ -267,6 +267,10 @@ declare namespace P {
          * The string key for the 'message' in the JSON object. Default: "msg".
          */
         messageKey?: string;
+        /**
+         * The string key to place any logged object under.
+         */
+        nestedKey?: string;
         /**
          * Enables pino.pretty. This is intended for non-production configurations. This may be set to a configuration
          * object as outlined in http://getpino.io/#/docs/API?id=pretty. Default: `false`.

types/pino/pino-tests.ts

@@ -177,6 +177,10 @@ const withTimeFn = pino({
     timestamp: pino.stdTimeFunctions.isoTime,
 });
 
+const withNestedKey = pino({
+    nestedKey: 'payload',
+});
+
 // Properties/types imported from pino-std-serializers
 const wrappedErrSerializer = pino.stdSerializers.wrapErrorSerializer((err: pino.SerializedError) => {
   return {...err, newProp: 'foo'};