Add separate GitHub workflow config for unit-testing java11 branch

- So as to use Java11 in the branch, while keep using Java8 in other branches

[#184142402]

.github/workflows/unit-test-java11.yml

@@ -0,0 +1,22 @@
+name: unit-test-java11
+
+on:
+  push:
+    branches:
+      - '**java11'
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Setup JDK
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'liberica'
+          java-version: '11'
+      - name: Build and test with Gradle
+        run: ./gradlew clean build

.github/workflows/unit-test.yml

@@ -1,6 +1,9 @@
 name: unit-test
 
-on: [push]
+on:
+  push:
+    branches-ignore:
+      - '**java11'
 
 permissions:
   contents: read