Remove the hover effect for inactive sash classes.

[cemalgnlts]

Hi,

If the sash class is disabled, it seems more correct not to show background-color on hover.

[codesandbox-ci]

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Sandbox	Source
constraints-dockview	Configuration
customheader-dockview	Configuration
demo-dockview	Configuration
dnd-dockview	Configuration
dockview-app	Configuration
editor-gridview	Configuration
events-dockview	Configuration
externaldnd-dockview	Configuration
floatinggroup-dockview	Configuration
fullwidthtab-dockview	Configuration
headeractions-dockview	Configuration
iframe-dockview	Configuration
keyboard-dockview	Configuration
layout-dockview	Configuration
lockedgroup-dockview	Configuration
nativeapp-dockview	Configuration
nested-dockview	Configuration
rendering-dockview	Configuration
resize-dockview	Configuration
resizecontainer-dockview	Configuration
simple-dockview	Configuration
simple-gridview	Configuration
simple-paneview	Configuration
tabheight-dockview	Configuration