Microsoft.AspNetCore.Http: Decorate priorFeature as nullable on StreamResponseBodyFeature ctor (#38875)

* Decorate priorFeature as nullable on StreamResponseBodyFeature ctor.

Author: CodeBlanch

src/Http/Http/src/PublicAPI.Unshipped.txt

@@ -1 +1,3 @@
 #nullable enable
+*REMOVED*Microsoft.AspNetCore.Http.StreamResponseBodyFeature.StreamResponseBodyFeature(System.IO.Stream! stream, Microsoft.AspNetCore.Http.Features.IHttpResponseBodyFeature! priorFeature) -> void
+Microsoft.AspNetCore.Http.StreamResponseBodyFeature.StreamResponseBodyFeature(System.IO.Stream! stream, Microsoft.AspNetCore.Http.Features.IHttpResponseBodyFeature? priorFeature) -> void

src/Http/Http/src/StreamResponseBodyFeature.cs

@@ -34,7 +34,7 @@ public StreamResponseBodyFeature(Stream stream)
     /// </summary>
     /// <param name="stream"></param>
     /// <param name="priorFeature"></param>
-    public StreamResponseBodyFeature(Stream stream, IHttpResponseBodyFeature priorFeature)
+    public StreamResponseBodyFeature(Stream stream, IHttpResponseBodyFeature? priorFeature)
     {
         Stream = stream ?? throw new ArgumentNullException(nameof(stream));
         PriorFeature = priorFeature;