Comment on “Geochemical evidences of seismo-volcanic unrests at the NW rift-zone of Tenerife, Canary Islands, inferred from diffuse CO2 emission” by Hernández P. A., Padilla G., Barrancos J., Melián G., Padrón E., Asensio-Ramos M., Rodríguez F., Pérez N. M., Alonso M., and Calvo D. [Bull Volcanol (2017) 79:30]