minor #19043 [WebLink] Adding missing "as" to style link header (weaverryan)

This PR was merged into the 6.4 branch.

Discussion
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[WebLink] Adding missing "as" to style link header

Hi!

The "as" is needed for preload. Notice that it is already included in the next example, but missing here (and there is no magic where the `$this->addLink()` method adds the `as`).

Cheers!

Commits
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822ea3a Adding missing "as" to style link header

Author: javiereguiluz

web_link.rst

@@ -164,7 +164,7 @@ You can also add links to the HTTP response directly from controllers and servic
         public function index(Request $request): Response
         {
             // using the addLink() shortcut provided by AbstractController
-            $this->addLink($request, new Link('preload', '/app.css'));
+            $this->addLink($request, (new Link('preload', '/app.css'))->withAttribute('as', 'style'));
 
             // alternative if you don't want to use the addLink() shortcut
             $linkProvider = $request->attributes->get('_links', new GenericLinkProvider());