fix: add 'Buffer' to webpack.ProvidePlugin list

Running the funding feature now using webpack crashes the app due to
Buffer not being available.

Signed-off-by: Nuno Alexandre <hi@nunoalexandre.com>

webpack.config.ts

@@ -92,6 +92,7 @@ function ui(_env: unknown, argv: Argv): webpack.Configuration {
     },
     plugins: [
       new webpack.ProvidePlugin({
+        Buffer: ["buffer", "Buffer"],
         process: "process",
       }),
       new HtmlWebpackPlugin({