IContentManager Unload extension method for IUrlReference can't be invoked in the 'extension' form

Release Type: Official Release

Version: 4.2.0.2232 and all prior versions when IUrlReference was added.

Platform(s): All

Describe the bug
Calling the following Unload extension method with an IUrlReference on this line won't work if called like:

IContentManager contentManager =...
IUrlReference urlReference = ...
contentManager.Unload(urlReference);

https://github.com/stride3d/stride/blob/256c47ba54bb1bc072d9adac397f34541ecd3072/sources/core/Stride.Core.Serialization/Serialization/UrlReferenceContentManagerExtenstions.cs#L114

This is because the IContentManager.Unload(object obj) is on the 'real' interface and will always take priority.
https://github.com/stride3d/stride/blob/256c47ba54bb1bc072d9adac397f34541ecd3072/sources/core/Stride.Core.Serialization/Serialization/Contents/IContentManager.cs#L69

When Unload with IUrlReference gets called this way, then the exception is thrown:
System.InvalidOperationException: 'Content not loaded through this ContentManager.'

Also, the UrlReferenceContentManagerExtenstions is incorrectly spelled (the extra t in extension).

Potential Solutions
Add void Unload(IUrlReference urlReference) on IContentManager
I don't think checking within void Unload(object obj) would be a good idea because there might potentially be a case where an UrlReference is somehow intentionally loaded/unloaded through ContentManager?

UrlReferenceContentManagerExtenstions would just be a breaking name change fix.

Workaround
Call ContentManagerExtenstions.Unload(contentManager, urlReference) or contentManager.Unload(urlReference.Url)

Start with sources/core/Stride.Core.Serialization/Serialization/UrlReferenceContentManagerExtenstions.cs at the Unload extension and sources/core/Stride.Core.Serialization/Serialization/Contents/IContentManager.cs at Unload(object). Verify the interface and extension overload behavior for IUrlReference, then confirm the corrected API name and direct contentManager.Unload(urlReference) call no longer throws Content not loaded through this ContentManager.