Fixed a build error

src/ImageSharp/Common/Extensions/StreamExtensions.cs

@@ -4,6 +4,9 @@
 using System;
 using System.IO;
 using SixLabors.ImageSharp.Memory;
+#if !SUPPORTS_SPAN_STREAM
+using System.Buffers;
+#endif
 
 namespace SixLabors.ImageSharp
 {

tests/ImageSharp.Tests/Metadata/Profiles/Exif/ExifProfileTests.cs

@@ -394,7 +394,7 @@ namespace SixLabors.ImageSharp.Tests
         public void ProfileToByteArray()
         {
             // Arrange
-            byte[] exifBytesWithoutExifCode = ExifConstants.LittleEndianByteOrderMarker;
+            byte[] exifBytesWithoutExifCode = ExifConstants.LittleEndianByteOrderMarker.ToArray();
             ExifProfile expectedProfile = CreateExifProfile();
             var expectedProfileTags = expectedProfile.Values.Select(x => x.Tag).ToList();