chore: reorganize build cli (#4389)

* initial commit

* refactor handle

* Make type checker happy

* Move handle to the top

* Restore --skip-flutter-doctor option

* replace self.target_platform by self.options.target_platform

* check skip_flutter_doctor flag from cli options

* Make pylance happy

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Co-authored-by: Feodor Fitsner <feodor@appveyor.com>

Author: ndonkoHenri