Version conflicts on process flutter_driver and screenshots dependencies

[HarminderSinghSandhu]

Because screenshots >=1.0.0 depends on process ^3.0.9 and every version of flutter_driver from sdk depends on process 4.2.1, screenshots >=1.0.0 is incompatible with flutter_driver from sdk.
So, because ad_app depends on both flutter_driver any from sdk and screenshots ^2.1.1, version solving failed.

[edwinludik]

screenshots does not support Nullsafety yet. Its a WIP: Compatibility with Dart 2.10.