updated integration instructions

Signed-off-by: Nigel Wright <nigel.wright@roamdigital.com>

docs/integrations/aws-s3/discovery.md

@@ -27,9 +27,9 @@ catalog:
 
 Note the `s3-discovery` type, as this is not a regular `url` processor.
 
-As this processor is not one of the default providers, you will also need to add the below:
+As this processor is not one of the default providers, you will also need to add the below to `packages/backend/src/plugins/catalog.ts`:
 
-```javascript
+```ts
 /* packages/backend/src/plugins/catalog.ts */
   
 import { AwsS3DiscoveryProcessor} from '@backstage/plugin-catalog-backend';