Correct typo in set-theoretic types doc (#13538)

Author: tjchambers

lib/elixir/pages/references/gradual-set-theoretic-types.md

@@ -62,7 +62,7 @@ The simplest way to reason about `dynamic()` in Elixir is that it is a range of
 
 However, by intersecting any type with `dynamic()`, we make the type gradual and therefore only a subset of the type needs to be valid. For instance, if you call `Integer.to_string(var)`, and `var` has type `dynamic() and (atom() or integer())`, the type system will not emit a warning, because `Integer.to_string/1` works with at least one of the types. This flexibility makes `dynamic()` excellent for typing existing code, because it will only emit warnings once it is certain the code will fail. For convenience, most programs will write `dynamic(atom() or integer())` instead of the intersection. They have the same behaviour.
 
-Once Elixir introduces typed function signatures, typed Elixir programs will behave as a statically typed code, unless the `dynamic()` type is used. This brings us to one last remark about dynamic types in Elixir: dyamic types are always at the root. For example, when you write a tuple of type `{:ok, dynamic()}`, Elixir will rewrite it to `dynamic({:ok, term()})`. While this has the downside that you cannot make part of a tuple/map/list gradual, only the whole tuple/map/list, it comes with the upside that dynamic is always explicitly at the root, making it harder to accidentally sneak `dynamic()` in a statically typed program.
+Once Elixir introduces typed function signatures, typed Elixir programs will behave as a statically typed code, unless the `dynamic()` type is used. This brings us to one last remark about dynamic types in Elixir: dynamic types are always at the root. For example, when you write a tuple of type `{:ok, dynamic()}`, Elixir will rewrite it to `dynamic({:ok, term()})`. While this has the downside that you cannot make part of a tuple/map/list gradual, only the whole tuple/map/list, it comes with the upside that dynamic is always explicitly at the root, making it harder to accidentally sneak `dynamic()` in a statically typed program.
 
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