docs(vscode): add disclaimer to the extension (#1047)

Author: alestiago

extensions/vscode/README.md

@@ -1,5 +1,7 @@
 [![Dart Frog Logo][logo_black]][dart_frog_link_light]
 
+> ✏️ Note: The extension is currently in the early stages, if you experience issues or have a recommendation we are eager to hear from you [here](https://github.com/VeryGoodOpenSource/dart_frog/issues/new/choose)!
+
 This is the [Dart Frog](https://dartfrog.vgv.dev/) [VS Code](https://code.visualstudio.com/) extension, which provides tools for effectively managing Dart Frog projects.
 
 Developed with 💙 by [Very Good Ventures][very_good_ventures_link] 🦄