Clarify support for icons from folder-based source (#3146)

Author: donnie-msft

docs/reference/nuspec.md

@@ -201,7 +201,7 @@ For example, you would add the following to your nuspec when creating a package
 For the MSBuild equivalent, take a look at [Packing an icon image file](msbuild-targets.md#packing-an-icon-image-file).
 
 > [!Tip]
-> You can specify both `icon` and `iconUrl` to maintain backward compatibility with sources that do not support `icon`. Visual Studio will support `icon` for packages coming from a folder-based source in a future release.
+> To maintain backward compatibility with clients and sources that don't yet support `icon`, specify both `icon` and `iconUrl`. Visual Studio supports `icon` for packages coming from a folder-based source.
 
 #### readme