Update dart_skills_lint dependency to e449787 and inherit target configuration (#9830)

Updates the pinned `dart_skills_lint` reference in `tool/pubspec.yaml` to commit hash `e4497873950727ee781fa411c1a2f624b1ec50c6` (version `0.3.0`). Refactors `tool/test/validate_skills_test.dart` to load configuration dynamically via `ConfigParser.loadConfig` and omit targeting overrides, enabling native path inheritance from `tool/dart_skills_lint.yaml`.
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pubspec.lock

diff --git a/pubspec.lock b/pubspec.lock
index 769f78d..2a6ed9a 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -213,11 +213,11 @@
     dependency: transitive
     description:
       path: "tool/dart_skills_lint"
-      ref: "2420128e11101002e2eac98eb90512103a388714"
-      resolved-ref: "2420128e11101002e2eac98eb90512103a388714"
+      ref: e4497873950727ee781fa411c1a2f624b1ec50c6
+      resolved-ref: e4497873950727ee781fa411c1a2f624b1ec50c6
       url: "https://github.com/flutter/skills"
     source: git
-    version: "0.2.0"
+    version: "0.3.0"
   dart_style:
     dependency: transitive
     description:

tool/pubspec.yaml

diff --git a/tool/pubspec.yaml b/tool/pubspec.yaml
index 68671b4..6768d1e 100644
--- a/tool/pubspec.yaml
+++ b/tool/pubspec.yaml
@@ -28,6 +28,6 @@
     git:
       url: https://github.com/flutter/skills
       path: tool/dart_skills_lint
-      ref: 2420128e11101002e2eac98eb90512103a388714
+      ref: e4497873950727ee781fa411c1a2f624b1ec50c6
   logging: ^1.1.1
   test: ^1.25.8

tool/test/validate_skills_test.dart

diff --git a/tool/test/validate_skills_test.dart b/tool/test/validate_skills_test.dart
index 1c44f8b..04736e7 100644
--- a/tool/test/validate_skills_test.dart
+++ b/tool/test/validate_skills_test.dart
@@ -7,6 +7,8 @@
 import 'package:logging/logging.dart';
 import 'package:test/test.dart';
 
+const String _configFilePath = 'dart_skills_lint.yaml';
+
 void main() {
   test('Validate DevTools Skills', () async {
     final Level oldLevel = Logger.root.level;
@@ -17,16 +19,10 @@
         });
 
     try {
-      // TODO(https://github.com/flutter/skills/issues/85): Update test
-      // to use dart_skills_lint.yaml for config when available.
-      final bool isValid = await validateSkills(
-        skillDirPaths: ['../.agents/skills'],
-        resolvedRules: {
-          'check-relative-paths': AnalysisSeverity.error,
-          'check-absolute-paths': AnalysisSeverity.error,
-          'check-trailing-whitespace': AnalysisSeverity.error,
-        },
+      final Configuration config = await ConfigParser.loadConfig(
+        path: _configFilePath,
       );
+      final bool isValid = await validateSkills(config: config);
       expect(
         isValid,
         isTrue,