applets/taskmanager: Reduce width of items when in horizontal panel
The width of taskmanager items is more than plasma 5 and looks odd. The reason is due to porting away from PlasmaCore.Theme.mSize(font).width and using Kirigami.Units.iconSizes.sizeForLabels.
I am not sure if using Kirigami.Units.iconSizes.sizeForLabels is right and have instead used Kirigami.Units.gridUnit according to the porting guide.
Before:
After:
Edited by Bacteria Dev