update jdk and deps-ckeck plugin

.drone.yml

@@ -15,25 +15,25 @@ trigger:
 steps:
   # test if it compiles correctly
   - name: build
-    image: maven:3-eclipse-temurin-16
+    image: maven:3-eclipse-temurin-21
     commands:
       - mvn verify --no-transfer-progress -DskipTests=true -Dmaven.javadoc.skip=true -B -V
 
   # run unit tests
   - name: test
-    image: maven:3-eclipse-temurin-16
+    image: maven:3-eclipse-temurin-21
     commands:
       - mvn test --no-transfer-progress -B -V
 
   # check maven dependencies
   - name: dependency-check
-    image: maven:3-eclipse-temurin-16
+    image: maven:3-eclipse-temurin-21
     commands:
       - mvn dependency-check:check --no-transfer-progress -B -V
 
   # run code analysis
   - name: code-analysis
-    image: maven:3-eclipse-temurin-16
+    image: maven:3-eclipse-temurin-21
     commands:
       - mvn sonar:sonar --no-transfer-progress -Dsonar.projectKey=$SONAR_PROJECT_KEY -Dsonar.host.url=$SONAR_INSTANCE_URL -Dsonar.login=$SONAR_LOGIN_KEY -B -V
     environment:
@@ -64,7 +64,7 @@ steps:
 
   # upload to maven repository
   - name: maven-deploy
-    image: maven:3-eclipse-temurin-16
+    image: maven:3-eclipse-temurin-21
     commands:
       - mvn deploy --no-transfer-progress -DskipTests=true -Dmaven.javadoc.skip=true -B -V -gs settings.xml -Dmaven.repo.username=$MAVEN_REPO_USERNAME -Dmaven.repo.password=$MAVEN_REPO_PASSWORD
     environment:

README.MD

@@ -23,7 +23,7 @@ Additionally available parameters are:
   - **verbose**: log every message that the bot receives, plus additional debugging messages. Very spammy and performance heavy.
   - **refresh**: force refresh the slash commands. This is useful in case there was a simple update to a command that did not drastically change it, so no changes are found at bootup (eg: fixing a typo in the command description).
 
-*Note: Java 16 or later is required.*
+*Note: Java 21 or later is required.*
   
 ## Initial setup  
   
@@ -45,4 +45,4 @@ behavior.
 This project uses the `x.y.z-releaseType` schema for releases.  
 Development builds are tagged as `x.y.z-SNAPSHOT` and sometimes pushed to the snapshots Maven repository.  
 Stable builds are tagged as `x.y.z` and always pushed to the releases Maven repository, by promoting the build on
-[Drone](https://drone.beatrice.wtf/). Currently, promoting stable builds is a manual process.
+[Drone](https://drone.beatrice.wtf/). Currently, promoting stable builds is a manual process.

pom.xml

@@ -9,8 +9,8 @@
     <version>0.5.20-SNAPSHOT</version>
 
     <properties>
-        <maven.compiler.source>16</maven.compiler.source>
-        <maven.compiler.target>16</maven.compiler.target>
+        <maven.compiler.source>21</maven.compiler.source>
+        <maven.compiler.target>21</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <sonar.dependencyCheck.htmlReportPath>./target/dependency-check-report.html</sonar.dependencyCheck.htmlReportPath>
         <sonar.dependencyCheck.jsonReportPath>./target/dependency-check-report.json</sonar.dependencyCheck.jsonReportPath>
@@ -144,7 +144,7 @@
             <plugin>
                 <groupId>org.owasp</groupId>
                 <artifactId>dependency-check-maven</artifactId>
-                <version>7.4.4</version>
+                <version>12.1.0</version>
                 <configuration>
                     <failBuildOnCVSS>8</failBuildOnCVSS>
                     <formats>