Adding call to endsValue in endObject

Adding call to endsValue in endObejct - was leading to malformed JSON with nested objects

Author: dougqh

dd-java-agent/src/main/java/datadog/trace/bootstrap/JsonBuffer.java

@@ -37,6 +37,8 @@ public JsonBuffer beginObject() {
   }
 
   public JsonBuffer endObject() {
+    endsValue();
+
     return write('}');
   }