don't ignore REUSE.toml in reuse annotate

[spaceone]

We want to add missing annotations via a pre-commit hook (see #1178) but pre-commit is limited to pass either no filename or all filenames.
While some files have a annotation via REUSE.toml, reuse annotate will nevertheless add the copyright header.

→ It would be good to have an CLI argument to not ignore REUSE.toml or make this the default behavior.