add example code generator

my_template/template/hooks/befoje.js

@@ -0,0 +1,8 @@
+module.exports = {
+  'generate:before': ({ asyncapi, templateParams = {} }) => {
+    // Modify the AsyncAPI document before generation
+    if (templateParams.version) {
+      asyncapi._json.info.version = templateParams.version;
+    }
+  }
+};