modified github actions to use Dart 3.8 to satisfy pubspec.yaml upper bound of <3.9.0 needed for analyzer version issues

Author: dave-doty

.github/workflows/dart.yml

@@ -13,8 +13,10 @@ jobs:
       - name: Checkout branch
         uses: actions/checkout@v4
 
-      - name: Setup Dart SDK  # This will use the latest version of dart unless specified otherwise.
+      - name: Setup Dart SDK  # Using Dart 3.8 to match pubspec.yaml constraint
         uses: dart-lang/setup-dart@v1  # https://github.com/dart-lang/setup-dart
+        with:
+          sdk: 3.8
 
       - name: Install dependencies
         run: dart pub get

.github/workflows/dart_formatting.yml

@@ -13,8 +13,10 @@ jobs:
       - name: Checkout branch
         uses: actions/checkout@v4
 
-      - name: Setup Dart SDK  # This will use the latest version of dart unless specified otherwise.
+      - name: Setup Dart SDK  # Using Dart 3.8 to match pubspec.yaml constraint
         uses: dart-lang/setup-dart@v1  # https://github.com/dart-lang/setup-dart
+        with:
+          sdk: 3.8
 
       - name: Install dependencies
         run: dart pub get

.github/workflows/gh-pages-dev.yml

@@ -20,8 +20,10 @@ jobs:
           ref: gh-pages
           path: gh-pages-repo
 
-      - name: Setup Dart SDK  # This will use the latest version of dart unless specified otherwise.
+      - name: Setup Dart SDK  # Using Dart 3.8 to match pubspec.yaml constraint
         uses: dart-lang/setup-dart@v1  # https://github.com/dart-lang/setup-dart
+        with:
+          sdk: 3.8
 
       - name: Install dependencies
         run: dart pub get

.github/workflows/gh-pages.yml

@@ -19,8 +19,10 @@ jobs:
           ref: gh-pages
           path: gh-pages-repo
 
-      - name: Setup Dart SDK  # This will use the latest version of dart unless specified otherwise.
+      - name: Setup Dart SDK  # Using Dart 3.8 to match pubspec.yaml constraint
         uses: dart-lang/setup-dart@v1  # https://github.com/dart-lang/setup-dart
+        with:
+          sdk: 3.8
 
       - name: Install dependencies
         run: dart pub get