Update README.md

Author: facontidavide

README.md

@@ -1,10 +1,10 @@
 ![License MIT](https://img.shields.io/github/license/BehaviorTree/BehaviorTree.CPP?color=blue)
-![Version](https://img.shields.io/badge/version-3.6-blue.svg)
+![Version](https://img.shields.io/badge/version-3.7-blue.svg)
 [![cmake](https://github.com/BehaviorTree/BehaviorTree.CPP/actions/workflows/cmake.yml/badge.svg)](https://github.com/BehaviorTree/BehaviorTree.CPP/actions/workflows/cmake.yml)
 [![ros1](https://github.com/BehaviorTree/BehaviorTree.CPP/workflows/ros1/badge.svg?branch=master)](https://github.com/BehaviorTree/BehaviorTree.CPP/actions?query=workflow%3Aros1)
 [![ros2](https://github.com/BehaviorTree/BehaviorTree.CPP/workflows/ros2/badge.svg?branch=master)](https://github.com/BehaviorTree/BehaviorTree.CPP/actions?query=workflow%3Aros2)
 [![LGTM Grade](https://img.shields.io/lgtm/grade/cpp/github/BehaviorTree/BehaviorTree.CPP)](https://lgtm.com/projects/g/BehaviorTree/BehaviorTree.CPP/context:cpp)
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+![Discourse topics](https://img.shields.io/discourse/topics?server=https%3A%2F%2Fdiscourse.behaviortree.dev)
 
 # BehaviorTree.CPP