Adds a tip about "Supermatter SLIVER" for random individual vocabulary (

#11113)

* Yes, Sliver.

* change tips

strings/sillytips.txt

@@ -46,3 +46,4 @@ If in doubt, blame the clown.
 Always remember that the mentors are there to help you. If you don't understand something, there's no shame in asking for help.
 Nobody suspects the mime.
 Purple is the sneakiest colour.
+There is no supermatter SILVER. There is only supermatter SLIVER.