fixing test for ref
MODIFY
tests/external/reproductions.repos.yaml
tests/external/reproductions.repos.yaml
# A bunch of external repos that reproduce something cool we care about
- name: LIGO Gravitational Waves
url: https://github.com/minrk/ligo-binder/
- ref: b8259dac9eb
+ ref: origin/b8259dac9eb
verify: python -c 'import matplotlib'

fixing test for ref