Update v0.3.x-to-v0.4.x.md

docs/migration/v0.3.x-to-v0.4.x.md

@@ -30,7 +30,7 @@ We refactored our icons which might add some breaking changes to current project
 We provide a cli tool to auto migrate your source code. Use this command in your repository:
 
 ```shell
-npx @db-ui/[email protected] migration --src=./src
+npx @db-ui/[email protected] migration --type=icon --src=./src
 ```
 
 Please check the changes made in your codebase afterwards, as this is mainly a simple search & replace and there might be unexpected changes of similar wordings to our icon names for any other methods, or further code occurrences that don't even refer to icons.