add mafft/align module to msa_alignment class

[mirpedrol]

This PR is to demonstrate how to add a new module to a class.

1. Add the name of the new module to the class YAML file
2. Open a PR
3. A GHA Update subworkflows is triggered to update the subworkflow: https://github.com/mirpedrol/class-modules/actions/runs/17101836896
4. The GHA will update the subworkflow and push a new commit: c80952c
5. The same GHA will generate an nf-test snapshot and commit the changes: 0c3321f
6. The code should be reviewed!
   • If you need to make changes, make sure to patch the subworkflow to take your modifications into account for following updates.
     You will have to provide the URL to your fork and the working branch:
     • For this PR (not a fork): nf-class subworkflows --branch add-new-module-to-class patch msa_alignment
     • In general: nf-class subworkflows --git-remote <YOUR_REMOTE> --branch <PR_BRANCH> patch <CLASS_NAME>