Summary:
The CSV importer used to generate non-unique edge IDs when
generating edges from multiple CSV files. This is incompatible with the
unique ID requirements introduced by the WAL. Tested and fixed in this
diff.
Reviewers: teon.banek, mferencevic
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D980
