Remove mock storages used in tests.
Impacts:
- swh-indexer
- swh-deposit
- swh-journal
- swh-loader-git
- swh-loader-mercurial
- swh-loader-core (named LoaderNoStorage)
- swh-loader-pypi
- swh-loader-svn
- swh-web
Migrated from T1307 (view on Phabricator)
Impacts:
Migrated from T1307 (view on Phabricator)