Here is how to get rid of the message properly
1. Sign out from System Preferences - Apple ID
If the notification is still visible, run from Terminal
Code:
defaults delete com.apple.systempreferences AttentionPrefBundleIDs;killall Dock
2. Disable SIP (Boot to macOS Recovery, from Terminal run
csrutil disable)
3. Boot into Catalina and from Terminal run
Code:
launchctl unload -w /System/Library/LaunchAgents/com.apple.followupd.plist
sudo launchctl unload -w /System/Library/LaunchAgents/com.apple.followupd.plist
4. Open AppStore and log in.