docs(): some tweaks to file upload

Author: kamilmysliwiec

content/techniques/file-upload.md

@@ -4,14 +4,14 @@ To handle file uploading, Nest provides a built-in module based on the [multer](
 
 > warning **Warning** Multer cannot process data which is not in the supported multipart format (`multipart/form-data`). Also, note that this package is not compatible with the `FastifyAdapter`.
 
-#### Use with Express (default)
-
-If you want to use the `Express.Multer.File` type for `@UploadedFile()` files, it is necessary to install the types:
+For better type safety, let's install Multer typings package:
 
 ```shell
 $ npm i -D @types/multer
 ```
 
+With this package installed, we can now use the `Express.Multer.File` type (you can import this type as follows: `import {{ '{' }} Express {{ '}' }} from 'express'`).
+
 #### Basic example
 
 To upload a single file, simply tie the `FileInterceptor()` interceptor to the route handler and extract `file` from the `request` using the `@UploadedFile()` decorator.