Add watch intro badge

Author: pbernet

README.md

@@ -1,5 +1,6 @@
 [![Sourcegraph](https://img.shields.io/badge/search-this%20repo-blue)](https://sourcegraph.com/github.com/pbernet/akka_streams_tutorial "Sourcegraph")
 [![NotebookLM](https://img.shields.io/badge/listen%20to-this%20repo-blue)](https://notebooklm.google.com/notebook/15ab2fde-4d85-40ed-a7cf-a6fc83223680/audio "NotebookLM")
+[![GolpoAI](https://img.shields.io/badge/watch-intro-blue)](https://video.golpoai.com/share/53934a0a-8971-43b6-93cc-217f6663bf28 "GolpoAI")
 [![Build Status](https://github.com/pbernet/akka_streams_tutorial/actions/workflows/ci.yml/badge.svg)](https://github.com/pbernet/akka_streams_tutorial/actions/workflows/ci.yml)
 [![Scala Steward](https://img.shields.io/badge/Scala_Steward-helping-blue.svg?style=flat&logo=data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAA4AAAAQCAMAAAARSr4IAAAAVFBMVEUAAACHjojlOy5NWlrKzcYRKjGFjIbp293YycuLa3pYY2LSqql4f3pCUFTgSjNodYRmcXUsPD/NTTbjRS+2jomhgnzNc223cGvZS0HaSD0XLjbaSjElhIr+AAAAAXRSTlMAQObYZgAAAHlJREFUCNdNyosOwyAIhWHAQS1Vt7a77/3fcxxdmv0xwmckutAR1nkm4ggbyEcg/wWmlGLDAA3oL50xi6fk5ffZ3E2E3QfZDCcCN2YtbEWZt+Drc6u6rlqv7Uk0LdKqqr5rk2UCRXOk0vmQKGfc94nOJyQjouF9H/wCc9gECEYfONoAAAAASUVORK5CYII=)](https://scala-steward.org)