[#38] container: Fix DelInfo owner type

It is not a 20-byte scripthash, it is a 25-byte slice
(prefix + script-hash + checksum).

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

container/container_contract.go

@@ -339,7 +339,7 @@ func Delete(containerID []byte, signature interop.Signature, publicKey interop.P
 }
 
 type DelInfo struct {
-	Owner interop.Hash160
+	Owner []byte
 	Epoch int
 }