4346 [google_sign_in_web] Update URL to google_sign_in package in README (cla: yes, waiting for tree to go green, p: google_sign_in, platform-web, last mile)

4372 Add false secret lists, and enforce ordering (cla: yes, waiting for tree to go green, p: google_maps_flutter, p: google_sign_in, platform-web)

4391 [google_sign_in] Use a transparent image as a placeholder for the GoogleUserCircleAvatar (cla: yes, waiting for tree to go green, p: google_sign_in, last mile)

4406 Fix order-dependant platform interface tests (cla: yes, waiting for tree to go green, p: file_selector, p: google_maps_flutter, p: google_sign_in, p: url_launcher, p: video_player, p: quick_actions)