[DOC] Update Sample Application to demonstrate correct way to initialize Maps in MauiProgram.cs

[mikelor]

Is there an existing issue for this?

• I have searched the existing issues

Did you read the "Reporting a bug" section on Contributing file?

• I have read the "Reporting a bug" section on Contributing file: https://github.com/CommunityToolkit/Maui/blob/main/CONTRIBUTING.md#reporting-a-bug

Current Behavior

The current code in MauiProgram.cs does not enclose the UseCommunityToolkitMaps("key") in a #ifdef WINDOWS directive.

The 2.0.1 Release of the Community Toolkit Maps component introduced a change that requires the #ifdef Windows directive when compiling a multiple platform application with Maps.

This can cause confusion for people trying to incorporate Maps into the application due to the fact that since Maui 8.0.10 now throws an exception on Windows when using the standard Maps component.

This can cause hours of wasted effort tracking down the cause of the exception.

Expected Behavior

The current Sample code would include the #ifdef compiler directive for WINDOWS around the .UseCommunityToolkitMaps("key") method.

Further Discussion

Unsure whether to add just the #ifdef WINDOWS directive or also include the #IFDEF IOS || ANDROID as well. If doing the latter, we would also want to update the appropriate platforms to include setting API Keys.

Steps To Reproduce

1. Add Maps support for Android by calling .UseMauiMaps().
2. Get an exception when running on Windows that Maps is not supported on Windows.

Link to public reproduction project repository

https://github.com/mikelor/CommunityToolkit-Maui/

Environment

- .NET MAUI CommunityToolkit: v9.0.2
- OS: Windows 11
- .NET MAUI: 8.0.70

Anything else?

No response