Add ability to set favicon through environment variable (#4665)

Envfile

@@ -13,6 +13,7 @@ variable :APP_PROTOCOL, :String, default: "http://"
 variable :COMMUNITY_NAME, :String, default: "DEV(local)"
 variable :MAIN_SOCIAL_IMAGE, :String, default: "https://thepracticaldev.s3.amazonaws.com/i/6hqmcjaxbgbon8ydw93z.png"
 variable :SITE_TWITTER_HANDLE, :String, default: "tbd"
+variable :FAVICON_URL, :String, default: "favicon.ico"
 
 # Logo
 variable :LOGO_SVG, :String, default: ""

app/views/layouts/application.html.erb

@@ -54,7 +54,7 @@
       <% end %>
       <%= yield(:page_meta) %>
       <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
-      <%= favicon_link_tag %>
+      <%= favicon_link_tag ApplicationConfig["FAVICON_URL"] %>
       <link rel="apple-touch-icon" href="<%= asset_path "apple-icon.png" %>">
       <link rel="apple-touch-icon" sizes="152x152" href="<%= asset_path "apple-icon-152x152.png" %>">
       <link rel="apple-touch-icon" sizes="180x180" href="<%= asset_path "apple-icon-180x180.png" %>">

app/views/layouts/internal.html.erb

@@ -8,7 +8,7 @@
   <meta name="description" content="">
   <meta name="author" content="">
   <%= csrf_meta_tags %>
-  <%= favicon_link_tag %>
+  <%= favicon_link_tag ApplicationConfig["FAVICON_URL"] %>
   <link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" integrity="sha384-wvfXpqpZZVQGK6TAh5PVlGOfQNHSoD2xbE+QkPxCAFlNEevoEH3Sl0sibVcOQVnN" crossorigin="anonymous">
 
   <title><%= controller_name %></title>

app/views/pages/shecoded.html.erb

@@ -5,7 +5,7 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <meta http-equiv="X-UA-Compatible" content="ie=edge" />
     <title>#SheCoded 👩🏿‍💻👩‍💻👩🏾‍💻 - DEV Community</title>
-    <%= favicon_link_tag %>
+    <%= favicon_link_tag ApplicationConfig["FAVICON_URL"] %>
     <style>
       * {
           padding: 0;