Maven: fix lister after docker-dev review.
Fixing the lister after docker-dev test runs:
- The last_update entry in ListedOrigins was undef, now returns a datetime object.
- The lister would produce an invalid origin (https) in the case of malformed scm poms. Now we check the visit_type before yielding scm entries to make sure we only throw valid types.
Test Plan
Added a test case for the invalid scm tag in POM file, as can happen on maven central (e.g. with sprova4j).
Migrated from D7052 (view on Phabricator)