Add since tag onto ExprWithItemFlags for "all itemflags" (#7786)

Add forgotton since tag

Author: Fusezion

src/main/java/ch/njol/skript/expressions/ExprWithItemFlags.java

@@ -24,7 +24,7 @@
 	"give player torch with hide placed on item flag",
 	"set {_item} to diamond sword with all item flags"
 })
-@Since("2.10")
+@Since("2.10, 2.11 (all itemflags)")
 public class ExprWithItemFlags extends SimpleExpression<ItemType> {
 
 	static {