doc: remove deprecation warning

Closes #393

next/language/packages.md

@@ -37,10 +37,6 @@ There are four different kinds of visibility for types in MoonBit:
 but users can only read the values of these types from outside, construction and mutation are not allowed
 - fully public types, declared with `pub(all)`. The outside world can freely construct, modify and read values of these types
 
-```{warning}
-Currently, the semantic of `pub` is `pub(all)`. But in the future, the meaning of `pub` will be ported to `pub(readonly)`.
-```
-
 In addition to the visibility of the type itself, the fields of a public `struct` can be annotated with `priv`,
 which will hide the field from the outside world completely.
 Note that `struct`s with private fields cannot be constructed directly outside,
@@ -116,10 +112,6 @@ Abstract trait is the default visibility. Only the name of the trait is visible
 Readonly traits are declared with `pub(readonly) trait`, their methods can be involked from outside, but only the current package can add new implementation for readonly traits.
 Finally, fully public traits are declared with `pub(open) trait`, they are open to new implementations outside current package, and their methods can be freely used.
 
-```{warning}
-Currently, `pub trait` defaults to `pub(open) trait`. But in the future, the semantic of `pub trait` will be ported to `pub(readonly)`.
-```
-
 Abstract and readonly traits are sealed, because only the package defining the trait can implement them.
 Implementing a sealed (abstract or readonly) trait outside its package result in compiler error.
 If you are the owner of a sealed trait, and you want to make some implementation available to users of your package,