IObjectSerializer docs are outdated

[shweaver-MSFT]

Doc link: https://docs.microsoft.com/en-us/windows/communitytoolkit/helpers/objectserializer

The IObjectSerializer docs are outdated and show an implementation based on the previous signatures, which used strings.

The new signatures use object instead, so the sample code won't actually compile.

I don't have a good example for what it should be, because the solution is not so straight forward with object over string.

[michael-hawker]

@RosarioPulella mind taking a look into this later?

[Rosuavio]

It seems this API changed in CommunityToolkit/WindowsCommunityToolkit#3702.
I am not sure if it makes more sense to change the API back as String -> T and T -> String seem like better representations of serialization. I know this purpose of this API is to be used with the storage helpers and its this was changed to better work with the storage helpers than perhaps we should rename the class so it can be less misleading.

Either way I made a PR updating the docs.

[michael-hawker]

Yeah, we updated to object, as the UWP API accepts object for primitives. So we made it broader so it could be agnostic of the end result for the basic SystemSerializer we ship in the Toolkit. Though in most cases you would be going to a string, but you could have some other DB or data store that just accepts other types, so that's why it's more generalized now.