Ioc doc needs updating

[nixtar]

Since the Ioc doc was last updated the MVVM toolkit has added an Ioc class to make using DI/Ioc a lot nicer then the examples given.
https://github.com/CommunityToolkit/dotnet/blob/main/CommunityToolkit.Mvvm/DependencyInjection/Ioc.cs

This makes the following statement no longer accurate:
The MVVM Toolkit doesn't provide built-in APIs to facilitate the usage of this pattern, as there already exist dedicated libraries specifically for this such as the Microsoft.Extensions.DependencyInjection package, which provides a fully featured and powerful DI set of APIs, and acts as an easy to setup and use IServiceProvider.

The examples given should also be reworked with this new functionality in mind.

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Document details

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• ID: 2cbff622-7688-e385-f5c3-e6a5639ce25f
• Version Independent ID: ceae3915-4fae-e5ae-bf42-65361f44de36
• Content: Ioc - Windows Community Toolkit
• Content Source: docs/mvvm/Ioc.md
• Product: community-toolkit
• GitHub Login: @Sergio0694
• Microsoft Alias: mhawker