upgraded docker build java version

Author: Taz03

application/build.gradle

@@ -18,7 +18,7 @@ repositories {
 var outputImage = 'togetherjava.org:5001/togetherjava/tjbot:' + System.getenv('BRANCH_NAME') ?: 'latest'
 
 jib {
-    from.image = 'eclipse-temurin:21'
+    from.image = 'eclipse-temurin:22'
     to {
         image = outputImage
         auth {