79486 [flutter_releases] Flutter Stable 2.0.4 Framework Cherrypicks (a: tests, cla: yes, engine, f: cupertino, f: material design, framework, team, tool)

79500 Correct misspellings throughout the codebase (a: tests, cla: yes, f: cupertino, f: material design, framework, team, tool, waiting for tree to go green)

79562 remove unnecessary trailing commas (cla: yes, f: cupertino, f: material design, framework)

79620 update CupertinoPicker.selectionOverlay to nullable (cla: yes, f: cupertino, framework, waiting for tree to go green)

79650 add trailing comma when argList is splitted (cla: yes, d: examples, f: cupertino, f: material design, framework, team, waiting for tree to go green)