add expr_2021 and pat_param to fragment_specifier (#266)

* add expr_2021 and pat_param to fragment_specifier

* chore: tree-sitter generate

Author: m4rch3n1ng

grammar.js

@@ -209,8 +209,8 @@ module.exports = grammar({
     ),
 
     fragment_specifier: _ => choice(
-      'block', 'expr', 'ident', 'item', 'lifetime', 'literal', 'meta', 'pat',
-      'path', 'stmt', 'tt', 'ty', 'vis',
+      'block', 'expr', 'expr_2021', 'ident', 'item', 'lifetime', 'literal', 'meta', 'pat',
+      'pat_param', 'path', 'stmt', 'tt', 'ty', 'vis',
     ),
 
     _tokens: $ => choice(