[mobile] Add Android BrowserStack test project back (#23551)
## Description
Follow-up for #23383 and #23474
* Adds android BrowserStack test back in
* Modifies MAUI csproj file to build into an APK
### Motivation and Context
There were 2 issues with the previous PRs:
1. The updated MAUI .csproj file configuration failed when building to
iOS and MacCatalyst. This caused problems in the packaging pipeline
because we build all C# projects in the .soln file in the packaging
pipeline. Removed the Mac & iOS build targets for now
3. The previous MAUI .csproj file configuration did not build into an
APK. It was missing the `<OutputType>` XAML tag and the Android package
type XAML tag.