PLAT-1214: Force rootless builds

There is currently no ideal why to detect when we are root but running
rootless.
For now just force rootless builds.

internal/builder/embedded/bkimage/workeropt.go

@@ -28,7 +28,7 @@ func (c *Client) createWorkerOpt() (opt base.WorkerOpt, err error) {
 	}
 
 	// worker executor
-	unprivileged := system.GetParentNSeuid() != 0
+	unprivileged := true
 	c.logger.V(1).Info(fmt.Sprintf("Executor running unprivileged: %t", unprivileged))
 
 	exeOpt := runcexecutor.Opt{