3496 [camera] Revert compileSdkVersion back to 29 (cla: yes, p: camera, platform-android, waiting for tree to go green)

3503 [camera] Removed obsolete example folder from camera root (cla: yes, p: camera, platform-android)

3526 [shared_preferences] Migrate main package to null-safety (cla: yes, p: shared_preferences, platform-android, platform-ios, platform-macos, platform-web)

3537 [camera] Fixes crash on takePicture() (cla: yes, p: camera, platform-android)

3558 [camera] Added timeout to Android pre-capture sequence (cla: yes, p: camera, platform-android)

3633 Make executor an instance property (cla: yes, p: shared_preferences, platform-android, waiting for tree to go green)