Yet another macOS High Sierra bug: Unlock App Store system preferences with any password

Less than two months ago, Apple users discovered a bug in macOS that allowed anyone to log in with root access. Apple apologized and fixed it quickly, but now users on Open Radar have found a similar (but far less severe) macOS password bug.If you're running macOS High Sierra, try this: 
Open System Preferences.
Click on App Store.
If the padlock is unlocked, click to lock it.
Click the padlock to unlock it.
In the prompt, enter your username and any password.The App Store preferences