Update Github workflow with JDK21 (#927)

**Motivation**
Since Java 21 is an LTS version released on September 19, 2023. We should update the CI Github build.

Result
Close #911

.github/workflows/actions_build.yml

@@ -16,7 +16,7 @@ concurrency:
 
 env:
   LC_ALL: "en_US.UTF-8"
-  BUILD_JDK_VERSION: "17"
+  BUILD_JDK_VERSION: "21"
 
 jobs:
   build:
@@ -28,7 +28,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-12, windows-latest]
-        java: [17]
+        java: [21]
         include:
           - java: 8
             os: ubuntu-latest
@@ -40,22 +40,22 @@ jobs:
           - java: 17
             os: ubuntu-latest
             min-java: 11
-          - java: 19
+          - java: 21
             os: ubuntu-latest
     steps:
     - uses: actions/checkout@v3
 
     - id: setup-build-jdk
       name: Set up build JDK ${{ env.BUILD_JDK_VERSION }}
-      uses: actions/setup-java@v3
+      uses: actions/setup-java@v4
       with:
         distribution: 'temurin'
         java-version: ${{ env.BUILD_JDK_VERSION }}
 
     - id: setup-test-jdk
       if: ${{ matrix.java != env.BUILD_JDK_VERSION }}
       name: Set up test JDK ${{ matrix.java }}
-      uses: actions/setup-java@v3
+      uses: actions/setup-java@v4
       with:
         distribution: 'temurin'
         java-version: ${{ matrix.java }}

build.gradle

@@ -138,9 +138,9 @@ allprojects {
     }
 }
 
-// Require to use JDK 17 when releasing.
+// Require to use JDK 21 when releasing.
 tasks.release.doFirst {
-    if (JavaVersion.current() != JavaVersion.VERSION_17) {
+    if (JavaVersion.current() != JavaVersion.VERSION_21) {
         throw new IllegalStateException("You must release using JDK 17.")
     }
 }

dependencies.toml

@@ -51,7 +51,7 @@ mockito = "4.11.0"
 nexus-publish-plugin = "2.0.0"
 node-gradle-plugin = "7.0.2"
 osdetector = "1.7.3"
-proguard = "7.3.1"
+proguard = "7.4.2"
 quartz = "2.3.2"
 shadow-gradle-plugin = "7.1.2"
 shiro = "1.3.2"