Use any instead of interface{} (#419)

Author: tmm1

docs/tutorial.md

@@ -32,9 +32,9 @@ Here's a list of all available value types in Tengo.
 | bytes | byte array | `[]byte` |
 | error | [error](#error-values) value | - |
 | time | time value | `time.Time` |
-| array | value array _(mutable)_ | `[]interface{}` |
+| array | value array _(mutable)_ | `[]any` |
 | immutable array | [immutable](#immutable-values) array | - |
-| map | value map with string keys _(mutable)_ | `map[string]interface{}` |
+| map | value map with string keys _(mutable)_ | `map[string]any` |
 | immutable map | [immutable](#immutable-values) map | - |
 | undefined | [undefined](#undefined-values) value | - |
 | function | [function](#function-values) value | - |