深色模式中，紫色颜色调整

Log: 主题活动色调整主题活动色调整
Task: https://pms.uniontech.com/zentao/task-view-40058.html
Change-Id: I8c2d73e38103585a4832cf3044f587e01851bbf1
Reviewed-on: http://gerrit.uniontech.com/c/dde-control-center/+/7185
Reviewed-by: <mailman@uniontech.com>
Reviewed-by: lvpeilong <lvpeilong@uniontech.com>
Tested-by: <mailman@uniontech.com>