Update src/content/guides/getting-started.mdx

Co-authored-by: Even Stensberg <[email protected]>

Author: jashtanna007

src/content/guides/getting-started.mdx

@@ -244,7 +244,7 @@ As of version 4, webpack doesn't require any configuration, but most projects wi
     |- index.js
 ```
 
-**webpack.config.js**
+**webpack.config.mjs**
 
 ```javascript
 import path from 'path';