Bump tag used to test requirements example
MODIFY
tests/external/reproductions.repos.yaml
tests/external/reproductions.repos.yaml
# Test that tags work + ref is added to tag if not present
- name: Binder Examples - Requirements
url: https://github.com/binder-examples/requirements
- ref: test
+ ref: python-3.7
verify: python -c 'import matplotlib'
# Test that custom channels and downgrades don't
# get blocked by pinning

Bump tag used to test requirements example