It's mentioned both in the article, and in the comments here where someone else thought it isn't mentioned.
They didn't use the acronym ("LISA"), but instead spelled out the entire thing.
>Researchers are now working on several next-generation LIGO-type observatories, both on Earth and, in space, the Laser Interferometer Space Antenna; [...]
https://www.esa.int/Science_Exploration/Space_Science/LISA_f...