add reg3 sponsor deck

data/23/events/reg3/index.toml

@@ -26,8 +26,8 @@ In the case of Prague we're proud of contributing towards a more nuanced underst
 #link = "https://"
 
 #[sponsors]
-#link = ""
-#range = "6k-96k EUR"
+link = "https://docsend.com/view/8v9b9qkpxgxsnp36"
+range = "2k-4k EUR"
 
 [registration]
 type = "tickets"