fix(ui5-illustrated-message): remove offensive characters (#4929)

* fix(ui5-illustrated-message): remove offensive characters

Problem:
There were 'Z' characters in some of the illustrations. They are now
considered offensive.

Solution:
'Z' characters are removed from the following illustrations:
- NoEntries (Spot/Dialog/Scene)
- NoData (Scene)
- NoNotifications (Spot/Dialog)
- TntNoApplications (Spot/Dialog/Scene)
- TntNoFlows (Spot/Dialog/Scene)
- TntNoUsers (Spot/Dialog/Scene)

* More illustrations are now politically correct:
- EmptyCalendar
- SimpleBell
- SleepingBell
- Tent

* fixed incorrect SVG ID

Author: plamenivanov91