Guix documentation says that `guix upgrade` is an alias for `guix package -u`,
but the latter can upgrade a list of packages, while the former fails.
## Steps to reproduce
1. guix pull
2. guix upgrade --dry-run
3. Pick two packages from the list shown in (2), say, packages A and B
4. guix upgrade A B
## Expected result
Packages A and B are upgraded.
## Unexpected result
Step 4 fails with the following message:
guix upgrade: error: B: extraneous argument
## System information
Using guix 0ae0efd with the Guix System.
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Luis Felipe López Acevedo
https://luis-felipe.gitlab.io/
