"gsettings": error=2, No such file or directory" running headless

[Tres Finocchiaro]

[ERROR] 2023-11-04T15:10:17,182 @ qz.utils.ShellUtilities:159
	IOException executing: [gsettings, get, org.gnome.desktop.interface, gtk-theme] envp: [...]
java.io.IOException: Cannot run program "gsettings": error=2, No such file or directory
	at java.lang.ProcessBuilder.start(Unknown Source) ~[?:?]
	at java.lang.ProcessBuilder.start(Unknown Source) ~[?:?]
	at java.lang.Runtime.exec(Unknown Source) ~[?:?]
	at java.lang.Runtime.exec(Unknown Source) ~[?:?]
	at qz.utils.ShellUtilities.execute(ShellUtilities.java:138) ~[qz-tray.jar:?]
	at qz.utils.UnixUtilities.isDarkMode(UnixUtilities.java:223) ~[qz-tray.jar:?]
	at qz.utils.SystemUtilities.setSystemLookAndFeel(SystemUtilities.java:498) ~[qz-tray.jar:?]
	at qz.common.TrayManager.<init>(TrayManager.java:114) ~[qz-tray.jar:?]
	at qz.ws.PrintSocketServer.lambda$runServer$0(PrintSocketServer.java:60) ~[qz-tray.jar:?]
	at java.awt.event.InvocationEvent.dispatch(Unknown Source) ~[?:?]
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source) ~[?:?]
	at java.awt.EventQueue$4.run(Unknown Source) ~[?:?]
	at java.awt.EventQueue$4.run(Unknown Source) ~[?:?]
	at java.security.AccessController.doPrivileged(Unknown Source) [?:?]
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source) [?:?]
	at java.awt.EventQueue.dispatchEvent(Unknown Source) [?:?]
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source) [?:?]
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source) [?:?]
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source) [?:?]
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source) [?:?]
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source) [?:?]
	at java.awt.EventDispatchThread.run(Unknown Source) [?:?]
Caused by: java.io.IOException: error=2, No such file or directory
	at java.lang.ProcessImpl.forkAndExec(Native Method) ~[?:?]
	at java.lang.ProcessImpl.<init>(Unknown Source) ~[?:?]
	at java.lang.ProcessImpl.start(Unknown Source) ~[?:?]
	... 22 more