47503 Roll engine 472197a8e932..854d5f8e9e74 (20 commits) (autoroller: commit, cla: yes)

47521 Add brightness to CupertinoNavigationBar (fixes #46216) (cla: yes, f: cupertino, framework)

47522  Use system default find in update_dart_sdk.sh (cla: yes, tool, waiting for tree to go green)

47523 Add Border.symmetric constructor (cla: yes, framework, waiting for tree to go green)

47547 Add CatmullRomCurve and CatmullRomSpline (cla: yes, framework, team)