fix(windows): use proper NuGet feed for canaries

[tido64]

Description

Use proper NuGet feed for canaries

Platforms affected

• Android
• iOS
• macOS
• visionOS
• Windows

Test plan

cd example
yarn install-windows-test-app --use-nuget
cat windows/NuGet.Config

Perform the commands above for the current version, and once again for canary version (run npm run set-react-version canary-windows).

For the current version, NuGet.Config should not contain https://pkgs.dev.azure.com/ms/react-native/_packaging/react-native-public/nuget/v3/index.json. For the canary build, it should.