✨(react) add fullWidth props to Button

Can be useful in many situations.

packages/react/src/components/Forms/Examples/index.stories.tsx

@@ -0,0 +1,9 @@
+import { Meta } from "@storybook/react";
+
+export default {
+  title: "Components/Forms/Examples",
+} as Meta;
+
+export const Login = () => {
+  return <div>DOUDOU</div>;
+};