Developers are directed to helpful documentation for existing obsoletions

[jeffhandley]

We have 114 [Obsolete] attributes that link to https://go.microsoft.com/fwlink/?linkid=14202, which is no longer relevant or helpful. The obsolete APIs should either link to relevant documentation topics or they should not have links embedded in their messages.

While updating these, we can consider using the new UrlFormat property that ObsoleteAttribute offers.

Per #56677:

AppDomain.SetDynamicBase and the methods at https://github.com/dotnet/runtime/blob/main/src/libraries/System.Private.CoreLib/src/System/AppDomain.cs#L214:L235 are marked as [Obsolete] with a warning of the form AppDomain.Foo has been deprecated. Please investigate the use of AppDomainSetup.Bar instead. https://go.microsoft.com/fwlink/?linkid=14202, but the corresponding property of AppDomainSetup does not exist, confusing developers that stumble upon these obsolete methods.

[dotnet-issue-labeler]

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