Add lib declaration for RegExp#unicodeSets (#57111)

src/compiler/commandLineParser.ts

@@ -233,6 +233,7 @@ const libEntries: [string, string][] = [
     ["esnext.weakref", "lib.es2021.weakref.d.ts"],
     ["esnext.decorators", "lib.esnext.decorators.d.ts"],
     ["esnext.object", "lib.esnext.object.d.ts"],
+    ["esnext.regexp", "lib.esnext.regexp.d.ts"],
     ["decorators", "lib.decorators.d.ts"],
     ["decorators.legacy", "lib.decorators.legacy.d.ts"],
 ];