Render a component with the <InputFile> component inside requires additional set up, that bUnit should provide out of the box.

The current solution is to provide a mock of a IOptions<RemoteBrowserFileStreamOptions> and configure the JSInterop to handle the <InputFile> components JSInterop invocation. E.g.

var optionsMock = Substitute.For<IOptions<RemoteBrowserFileStreamOptions>>();
Services.AddSingleton<IOptions<RemoteBrowserFileStreamOptions>>(optionsMock);
JSInterop.SetupVoid("Blazor._internal.InputFile.init", x => true);

This will allow the component to render, but additional steps might be needed to test the "input" part of the component.

Related: #314