Make `rake gitlab:artifacts:migrate` compatible with any kinds of artifacts

Problem

Today, rake gitlab:artifacts:migrate can migrate file_type: artifact or metadata artifacts from local storage to object storage. However, we recently introduced the other kinds of artifact such as trace, codequality, etc, and users should be able to migrate these kinds of artifacts as well.

This issue has to be done after https://gitlab.com/gitlab-org/gitlab-ce/issues/58595.

Proposal

Fix lib/tasks/gitlab/artifacts/migrate.rake

/cc @ahanselka