Implement JSON security context serializer (new default) - smaller info and human readable (#2652)

keeps backward compatibility by being able to fallback to JAVA_SERIALIZATION

+ fix DMF messages with status code

Signed-off-by: Avgustin Marinov <Avgustin.Marinov@bosch.com>

hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/TestConfiguration.java

@@ -146,7 +146,7 @@ public class TestConfiguration implements AsyncConfigurer {
 
     @Bean
     SecurityContextSerializer securityContextSerializer() {
-        return SecurityContextSerializer.JAVA_SERIALIZATION;
+        return SecurityContextSerializer.JSON_SERIALIZATION;
     }
 
     @Bean

hawkbit-repository/hawkbit-repository-test/src/main/java/org/eclipse/hawkbit/repository/test/util/AbstractIntegrationTest.java

@@ -125,6 +125,7 @@ public abstract class AbstractIntegrationTest {
 
     protected static final URI LOCALHOST = URI.create("http://127.0.0.1");
     protected static final int DEFAULT_TEST_WEIGHT = 500;
+    @SuppressWarnings("java:S1068") // used for tests only, no need of secure random
     protected static final Random RND = new Random();
 
     /**