Polish DefaultDockerInitContext

Author: geoand

test-framework/junit5/src/main/java/io/quarkus/test/junit/launcher/DockerContainerLauncherProvider.java

@@ -155,8 +155,8 @@ static class DefaultDockerInitContext extends DefaultInitContextBase
         private final Map<Integer, Integer> additionalExposedPorts;
         private final Optional<String> entryPoint;
         private final List<String> programArgs;
-        private Map<String, String> labels;
-        private Map<String, String> volumeMounts;
+        private final Map<String, String> labels;
+        private final Map<String, String> volumeMounts;
 
         public DefaultDockerInitContext(int httpPort, int httpsPort, Duration waitTime, String testProfile,
                 List<String> argLine, Map<String, String> env,