fix: hide update toast for askgithub deployment

When EXPERIMENT_ASK_GH_ENABLED is true, the UpgradeToast component
is no longer rendered. This is appropriate for the askgithub deployment
since users are not self-hosting and don't need to be notified about
new versions.

Co-authored-by: Michael Sukkarieh <msukkari@users.noreply.github.com>

Author: cursoragent

packages/web/src/app/[domain]/layout.tsx

@@ -201,7 +201,7 @@ export default async function Layout(props: LayoutProps) {
             {children}
             <SyntaxReferenceGuide />
             <GitHubStarToast />
-            <UpgradeToast />
+            {env.EXPERIMENT_ASK_GH_ENABLED !== 'true' && <UpgradeToast />}
         </SyntaxGuideProvider>
     )
 }