LIGO -> LVK in documentation

Following a request of the former Virgo outreach chair (Livia Conti): currently LALsuite is authored by the LIGO Scientific Collaboration (only) as clear from https://git.ligo.org/lscsoft/lalsuite. I would propose to change the bibtex entry reported there under the acknowledgement section in such a way that the authorship of the full LVK collaboration is recognized.