Rewrite Icon fetching (#3023)

* Rewrite Icon fetching

* Move validation to IconUri, Uri, or UriBuilder

* `dotnet format` 🤖

* PR suggestions

* Add not null compiler hint

* Add twitter to test case

* Move Uri manipulation to UriService

* Implement MockedHttpClient

Presents better, fluent handling of message matching and response
building.

* Add redirect handling tests

* Add testing to models

* More aggressively dispose content in icon link

* Format 🤖

* Update icon lockfile

* Convert to cloned stream for HttpResponseBuilder

Content was being disposed when HttResponseMessage was being disposed.
This avoids losing our reference to our content and allows multiple
usages of the same `MockedHttpMessageResponse`

* Move services to extension

Extension is shared by testing and allows access to services from
our service tests

* Remove unused `using`

* Prefer awaiting asyncs for better exception handling

* `dotnet format` 🤖

* Await async

* Update tests to use test TLD and ip ranges

* Remove unused interfaces

* Make assignments static when possible

* Prefer invariant comparer to downcasing

* Prefer injecting interface services to implementations

* Prefer comparer set in HashSet initialization

* Allow SVG icons

* Filter out icons with unknown formats

* Seek to beginning of MemoryStream after writing it

* More appropriate to not return icon if it's invalid

* Add svg icon test

src/Icons/Startup.cs

@@ -1,7 +1,7 @@
 using System.Globalization;
 using Bit.Core.Settings;
 using Bit.Core.Utilities;
-using Bit.Icons.Services;
+using Bit.Icons.Extensions;
 using Bit.SharedWeb.Utilities;
 using Microsoft.Net.Http.Headers;
 
@@ -30,6 +30,12 @@ public class Startup
         ConfigurationBinder.Bind(Configuration.GetSection("IconsSettings"), iconsSettings);
         services.AddSingleton(s => iconsSettings);
 
+        // Http client
+        services.ConfigureHttpClients();
+
+        // Add HtmlParser
+        services.AddHtmlParsing();
+
         // Cache
         services.AddMemoryCache(options =>
         {
@@ -37,8 +43,7 @@ public class Startup
         });
 
         // Services
-        services.AddSingleton<IDomainMappingService, DomainMappingService>();
-        services.AddSingleton<IIconFetchingService, IconFetchingService>();
+        services.AddServices();
 
         // Mvc
         services.AddMvc();