Update rules.json and adjust test. (#4627)

* Adjust message

* try json

* fix

test/verify_machine_json_test.dart

@@ -10,12 +10,15 @@ import 'package:test/test.dart';
 import '../tool/machine.dart';
 
 void main() {
-  test('ensure `rules.json` is up to date', () async {
+  test("ensure 'rules.json' is up to date", () async {
     var rulesFilePath = path.join('tool', 'machine', 'rules.json');
     var onDisk = File(rulesFilePath).readAsStringSync();
     var generated = await generateRulesJson();
-    expect(generated, onDisk, reason: '''`rules.json` is out of date.
-  Regenerate by running `dart tool/machine.dart -w`
-''');
+    expect(
+      generated,
+      onDisk,
+      reason: "'rules.json' is out of date. Regenerate by running "
+          '`dart tool/machine.dart -w`',
+    );
   });
 }

tool/machine/rules.json

@@ -2610,7 +2610,7 @@
     "state": "stable",
     "incompatible": [],
     "sets": [],
-    "fixStatus": "noFix",
+    "fixStatus": "hasFix",
     "details": "Top-level members and static members in an executable library should be used\ndirectly inside this library.  An executable library is a library that contains\na `main` top-level function or that contains a top-level function annotated with\n`@pragma('vm:entry-point')`).  Executable libraries are not usually imported\nand it's better to avoid defining unused members.\n\nThis rule assumes that an executable library isn't imported by other files\nexcept to execute its `main` function.\n\n**BAD:**\n\n```dart\nmain() {}\nvoid f() {}\n```\n\n**GOOD:**\n\n```dart\nmain() {\n  f();\n}\nvoid f() {}\n```\n\n",
     "sinceDartSdk": "2.19.0"
   },