fix: add a SerializerFactory function that allows to create serializer without specifying the config (taking the default config)

[MaillPierre]

Adds to the SerializerFactory interface:

    /**
     * Creates a new RDF serializer for the specified format and model.
     *
     * @param format The {@link RDFFormat} to use for serialization.
     * @param model  The {@link Model} to be serialized.
     * @return A new instance of an RDF serializer for the specified format and
     *         model.
     */
    RDFSerializer createSerializer(RDFFormat format, Model model);

adds to the SerializerFactory class a function that will call the constructor of each serializer either through its constructor without config, or if it is not available, by generating a default config.

[abdessamad-abdoun]

J’ai profité de la correction de l’erreur Sonar pour nettoyer le package next dans les tests