Adds Default Implementation of Init for Typed Startup

Because an `IWebHostBuilder` can exit `CreateWebHostBuilder` in a
usable state, `Init` may not be necessary to override in a client's
entry point.

Author: chrisoverzero

Libraries/src/Amazon.Lambda.AspNetCoreServer/APIGatewayProxyFunction{TStartup}.cs

@@ -13,5 +13,10 @@ public abstract class APIGatewayProxyFunction<TStartup> : APIGatewayProxyFunctio
         /// <inheritdoc/>
         protected override IWebHostBuilder CreateWebHostBuilder() =>
             base.CreateWebHostBuilder().UseStartup<TStartup>();
+
+        /// <inheritdoc/>
+        protected override void Init(IWebHostBuilder builder)
+        {
+        }
     }
 }

Libraries/test/TestWebApp/Controllers/BinaryContentController.cs

@@ -1,5 +1,5 @@
-using System.IO;
 using Microsoft.AspNetCore.Mvc;
+using static System.Net.Mime.MediaTypeNames;
 
 namespace TestWebApp.Controllers
 {
@@ -14,7 +14,7 @@ public IActionResult Get([FromQuery] string firstName, [FromQuery] string lastNa
             for (int i = 0; i < bytes.Length; i++)
                 bytes[i] = (byte)i;
 
-            return base.File(bytes, LambdaFunction.BinaryContentType);
+            return base.File(bytes, Application.Octet);
         }
     }
-}
+}

Libraries/test/TestWebApp/LambdaFunction.cs

@@ -1,19 +1,8 @@
-using System.IO;
-
-using Amazon.Lambda.AspNetCoreServer;
-using Microsoft.AspNetCore.Hosting;
+using Amazon.Lambda.AspNetCoreServer;
 
 namespace TestWebApp
 {
     public class LambdaFunction : APIGatewayProxyFunction<Startup>
     {
-        public const string BinaryContentType = "application/octet-stream";
-
-        protected override void Init(IWebHostBuilder builder)
-        {
-            builder
-                .UseApiGateway()
-                .UseContentRoot(Directory.GetCurrentDirectory());
-        }
     }
 }