CcListRow: the secondary label is almost unreadable if the row is insensitive

Affected version

46.beta.2/gnome-control-center-45.2-1.fc39.x86_64

Description

CcListRow has a secondary label at the right that has the .dim-label style class. The problem is that when CcListRow is insensitive, the disabled opacity is also applied to the secondary label, making the text to show even more dimmed.

Row insensitive; secondary label with .dim-label	Row insensitive; secondary label without .dim-label

(Date & Time row is a CcListRow starting with Settings 46)

When CcListRow is insensitive, I think the secondary label shouldn't have the .dim-label style class. This will improve contrast and readability.