feat: adapt buildRun to properly open macOS apps

[szymonrybczak]

Summary:

Related: #2217

Adapts buildRun function to properly open macOS apps. If the platform is macos, we're executing this command to start app:

❯ open "/path/to/app"

This PR will allows us to seamlessly remove local-cli from react-native-macos and replace it with the this implementation.

Test Plan:

1. Clone the repository and do all the required steps from the Contributing guide
2. Run this command:

node /path/to/react-native-cli/packages/cli/build/bin.js run-ios

Should work the same

Checklist

• Documentation is up to date to reflect these changes.
• Follows commit message convention described in CONTRIBUTING.md

[thymikee]

@szymonrybczak can you please rebase now that installing in opening are split?

[szymonrybczak]

E2E tests are failing due to the problem with boost pod, more context: react/react-native#42109. As for now there's a workaround with adding patch, but we cannot do it here, since we're creating new project.