tests: Fix failures after test_storage renaming to storage_tests
Module was renamed but not its imports.
Also move the round_to_milliseconds function to the storage.utils module.
Migrated from D3817 (view on Phabricator)
Staging instance, all changes can be removed at any time
Module was renamed but not its imports.
Also move the round_to_milliseconds function to the storage.utils module.
Migrated from D3817 (view on Phabricator)