Extension random() to select random element from a collection

Fixes #KT-15539

libraries/stdlib/common/src/generated/_Maps.kt

@@ -16,6 +16,7 @@ package kotlin.collections
 import kotlin.*
 import kotlin.text.*
 import kotlin.comparisons.*
+import kotlin.random.*
 
 /**
  * Returns a [List] containing all key-value pairs.