[flutter_tools] fix instructions to disable CLI animations (#139094)

Fixes https://github.com/flutter/flutter/issues/139011

packages/flutter_tools/lib/src/features.dart

@@ -156,12 +156,14 @@ const Feature flutterWebWasm = Feature(
   ),
 );
 
+const String kCliAnimationsFeatureName = 'cli-animations';
+
 /// The [Feature] for CLI animations.
 ///
 /// The TERM environment variable set to "dumb" turns this off.
 const Feature cliAnimation = Feature.fullyEnabled(
   name: 'animations in the command line interface',
-  configSetting: 'cli-animations',
+  configSetting: kCliAnimationsFeatureName,
 );
 
 /// Enable native assets compilation and bundling.

packages/flutter_tools/lib/src/reporting/first_run.dart

@@ -36,7 +36,8 @@ const String _kFlutterFirstRunMessage = '''
   ║ See Google's privacy policy:                                               ║
   ║ https://policies.google.com/privacy                                        ║
   ║                                                                            ║
-  ║ To disable animations in this tool, use 'flutter config --no-animations'.  ║
+  ║ To disable animations in this tool, use                                    ║
+  ║ 'flutter config --no-cli-animations'.                                      ║
   ╚════════════════════════════════════════════════════════════════════════════╝
 ''';
 

packages/flutter_tools/test/general.shard/reporting/first_run_test.dart

@@ -4,6 +4,7 @@
 
 import 'package:file/memory.dart';
 import 'package:flutter_tools/src/base/logger.dart';
+import 'package:flutter_tools/src/features.dart';
 import 'package:flutter_tools/src/persistent_tool_state.dart';
 import 'package:flutter_tools/src/reporting/first_run.dart';
 
@@ -16,6 +17,12 @@ void main() {
     expect(messenger.licenseTerms, contains('Welcome to Flutter'));
   });
 
+  testWithoutContext('FirstRunMessenger informs user how to disable animations', () {
+    final FirstRunMessenger messenger = setUpFirstRunMessenger(redisplayWelcomeMessage: false);
+
+    expect(messenger.licenseTerms, contains('flutter config --no-$kCliAnimationsFeatureName'));
+  });
+
   testWithoutContext('FirstRunMessenger requires redisplay if it has never been run before', () {
     final FirstRunMessenger messenger = setUpFirstRunMessenger();