preview preparation needs to pass list of active data to children (#280)

Co-authored-by: Dominik Demuth <dominik.demuth@physik.tu-darmstadt.de>
Reviewed-on: IPKM/nmreval#280

src/gui_qt/main/mainwindow.py

@@ -12,7 +12,7 @@ from nmreval.lib.logger import logger
 from nmreval.io.sessionwriter import NMRWriter
 
 from .management import UpperManagement
-from ..lib.logger import ConsoleDock, QTextHandler
+from ..lib.logger import QTextHandler
 from ..Qt import QtGui, QtPrintSupport
 from ..data.shift_graphs import QShift
 from ..data.signaledit import QPreviewDialog, QBaselineDialog