refactor(ui): rename the small favicons to icons

There is no need to distinguish between "Android icons" and favicons.

internal/template/templates/common/layout.html

@@ -14,11 +14,8 @@
     <meta name="referrer" content="no-referrer">
     <meta name="google" content="notranslate">
 
-    <!-- Favicons -->
-    <link rel="icon" type="image/png" sizes="16x16" href="{{ route "appIcon" "filename" "favicon-16.png" }}">
-    <link rel="icon" type="image/png" sizes="32x32" href="{{ route "appIcon" "filename" "favicon-32.png" }}">
-
-    <!-- Android icons -->
+    <link rel="icon" type="image/png" sizes="16x16" href="{{ route "appIcon" "filename" "icon-16.png" }}">
+    <link rel="icon" type="image/png" sizes="32x32" href="{{ route "appIcon" "filename" "icon-32.png" }}">
     <link rel="icon" type="image/png" sizes="128x128" href="{{ route "appIcon" "filename" "icon-128.png" }}">
     <link rel="icon" type="image/png" sizes="192x192" href="{{ route "appIcon" "filename" "icon-192.png" }}">