fix typo and adjust app name to stick to the official template

Author: vrobert78

sites/platform/src/guides/ibexa/fastly.md

@@ -10,19 +10,19 @@ description: |
 
 ## Remove Varnish configuration
 
-In Ibexa DXP, Varnish is enabled by default when deploying on {{% vendor/name %}}
+In Ibexa DXP, Varnish is enabled by default when deploying on {{% vendor/name %}}.  
 To use Fastly, Varnish must be disabled:
 
 - Remove environment variable `TRUSTED_PROXIES: "REMOTE_ADDR"` in [`{{< vendor/configfile "app" >}}](https://github.com/ezsystems/ezplatform/blob/master/.platform.app.yaml)
 - Remove the Varnish service in [`{{< vendor/configfile "services" >}}`](https://github.com/ezsystems/ezplatform/blob/master/.platform/services.yaml)
 - In [`{{< vendor/configfile "routes" >}}`](https://github.com/ezsystems/ezplatform/blob/master/.platform/routes.yaml),
-   change routes to use `myapp` instead of the `varnish` service you removed in previous step:
+   change routes to use `app` instead of the `varnish` service you removed in previous step:
 
 ```diff {no-copy="true"}
  "https://{default}/":
      type: upstream
 -     upstream: "varnish:http"
-+     upstream: "myapp:http"
++     upstream: "app:http"
 ```
 
 ## Setting up Ibexa DXP to use Fastly