* fix: Networktype null safety issues
Networktype returns nulls when the connectivity result is vpn resulting to null safety issues.
Implemented a case for when the connectivity result is vpn to resolve this issue.
* chore: update connectivity_plus_platform_interface ^1.2.2
* chore: update network state on Rust side
Co-authored-by: Lucas.Xu <lucas.xu@appflowy.io>