Fix pwa showcase test

Author: rossta

app/content/layouts/showcase.html.erb

@@ -1,6 +1,6 @@
 ---
 title: Progressive Web Apps on Rails Showcase
-layout: showcase
+layout: article
 ---
 <section class="pwa:hidden">
   <h2 class="anchor text-xl text-joy-text font-bold mb-2">How to use this resource</h2>

app/content/pages/pwa-showcase.html.erb

@@ -6,9 +6,9 @@
   transform: translateX(-50%);
 
   width: max-content;
+}
 
-  &__message {
-    @apply text-sm p-4 text-white rounded-md font-semibold bg-joy-bg-active;
-    animation: appear-then-fade 4s both;
-  }
+.flash__message {
+  @apply text-sm p-4 text-white rounded-md font-semibold bg-joy-bg-active;
+  animation: appear-then-fade 4s both;
 }

app/javascript/css/components/flash.css

@@ -8,11 +8,7 @@
   end
 
   it "renders the Install to Homescreen button" do
-    Flipper.enable(:pwa_showcase_navigation)
-
-    visit "/"
-
-    click_link "Progress Web Apps on Rails Showcase"
+    visit "/pwa-showcase"
 
     expect(page).to have_button("Install to Homescreen")
   end
@@ -23,11 +19,8 @@
     end
 
     it "renders the Install to Homescreen button" do
-      Flipper.enable(:pwa_showcase_navigation)
-
-      visit "/"
+      visit "/pwa-showcase"
 
-      click_link "Progress Web Apps on Rails Showcase"
       click_link "Install to Homescreen"
 
       expect(page).to have_content("PWA installation is not currently supported in Firefox on desktop.")