Remove link to upstream documentation

Author: fredden

src/cloud/project/magento-app-properties.md

@@ -123,7 +123,7 @@ You can fine-tune your `locations` configuration using the following key values
 | ---------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `allow`    | Serve files that do not match "rules". Default value = `true`                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
 | `expires`  | Set the number of seconds to cache content in the browser. This key enables the `cache-control` and `expires` headers for static content. If this value is not set, the `expires` directive and resulting headers are not included when serving static content files. A negative 1 (`-1`) value results in no caching and is the default value. You can express time value with the following units:  `ms` (milliseconds), `s` (seconds), `m` (minutes), `h` (hours), `d` (days), `w` (weeks), `M` (months, 30d), or `y` (years, 365d) |
-| `headers` | List HTTP headers that should be sent with all files served from this location. See [the documentation at https://docs.platform.sh/ for details](https://docs.platform.sh/configuration/app/web.html#how-can-i-control-the-headers-sent-with-my-files). |
+| `headers` | Set custom headers, such as `X-Frame-Options`, for static content served from this location. |
 | `index`    | List the static files to serve your application, such as the `index.html` file. This key expects a collection. This only works if access to the file or files is "allowed" by the `allow` or `rules` key for this location.                                                                                                                                                                                                                                                                                                            |
 | `rules`    | Specify overrides for a location. Use a regular expression to match a request. If an incoming request matches the rule, then regular handling of the request is overridden by the keys used in the rule.                                                                                                                                                                                                                                                                                                                               |
 | `passthru` | Set the URL used in the event that a static file or PHP file cannot be found. Typically, this URL is the front controller for your applications, such as `/index.php` or `/app.php`.                                                                                                                                                                                                                                                                                                                                                   |