ci: update java

.github/workflows/dart.yml

@@ -11,7 +11,8 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-java@v2.5.0
         with:
-          java-version: '12.x'
+          distribution: 'temurin'
+          java-version: '11'
       - uses: subosito/flutter-action@v2.3.0
       - name: Version
         run: flutter doctor -v
@@ -20,4 +21,4 @@ jobs:
       - name: Format
         run: flutter format -n --set-exit-if-changed .
       - name: Linter
-        run: flutter analyze
+        run: flutter analyze