remove usage of private modules (#4664)

packages/html-internal-macro/src/lib.rs

@@ -1,8 +1,8 @@
 use proc_macro::TokenStream;
 
 use convert_case::{Case, Casing};
+use proc_macro2::TokenStream as TokenStream2;
 use quote::{quote, ToTokens, TokenStreamExt};
-use syn::__private::TokenStream2;
 use syn::parse::{Parse, ParseStream};
 use syn::punctuated::Punctuated;
 use syn::{braced, parse_macro_input, Ident, Token};