Add a reference to es2021 in the command line parser

Author: orta

src/compiler/commandLineParser.ts

@@ -71,6 +71,7 @@ namespace ts {
         ["es2021.promise", "lib.es2021.promise.d.ts"],
         ["es2021.string", "lib.es2021.string.d.ts"],
         ["es2021.weakref", "lib.es2021.weakref.d.ts"],
+        ["es2021.intl", "lib.es2021.intl.d.ts"],
         ["esnext.array", "lib.es2019.array.d.ts"],
         ["esnext.symbol", "lib.es2019.symbol.d.ts"],
         ["esnext.asynciterable", "lib.es2018.asynciterable.d.ts"],