64432 Reland “Make sure all isolates start during flutter driver tests” (a: tests, cla: yes, d: examples, framework, team, waiting for tree to go green)

64519 Re-enable image_list test with updated certificate(good for 3650 days). (cla: yes, d: examples, team)

64795 Add sample code to RotationTransition (cla: yes, d: api docs, d: examples, documentation, framework, waiting for tree to go green)

64984 Flutter stable framework 1.20.3 cherrypicks (a: internationalization, cla: yes, d: examples, engine, f: material design, framework, team, tool)

f: scrolling - 16 pull request(s)