1. Department of Physics, Astrophysics Group, Imperial College London, Prince Consort Rd, London SW7 2AZ, UK
2. Department of Physics and Astronomy, the University of British Columbia, 6244 Agricultural Road, Vancouver, BC V6T 1Z1, Canada
3. Imperial Centre for Inference and Cosmology, Astrophysics Group, Blackett Laboratory, Prince Consort Rd, London SW7 2AZ, UK
4. Data Science Institute, William Penney Laboratory, Imperial College London, London SW7 2AZ, UK
5. Department of Mathematics, Statistics Section, Huxley Building, South Kensington Campus, Imperial College London, London SW7 2AZ, UK
6. Bay House school & Sixth Form, Gomer lane, Gosport, Hampshire PO12 2QP, UK
7. Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK