Add docs for CLI rename slug task

[anvit]

No description provided.

[fiver-watson]

Hi! Looks good overall - found one important typo to fix, and also added a few suggestions you can take or leave.

One of those was to add a SEEALSO admonition with some links to related content throughout the docs. If you wanted to add links back to this section in those related areas, you'd find them at the following spots

Generate slugs task

It's right above, but it's also long, has an important overview of how slugs work in AtoM, and people tend to navigate via links and search rather than reading sequentially, so i think it's worth linking. There's already a TIP admonition linking to another section that you could expand, or replace with a more general SEEASLO admonition, at:

• https://github.com/artefactual/atom-docs/blob/2.7/admin-manual/maintenance/cli-tools.rst?plain=1#L1086

Rename module

• https://github.com/artefactual/atom-docs/blob/2.7/user-manual/add-edit-content/archival-descriptions.rst?plain=1#L1265

Generate description permalinks from setting

• https://github.com/artefactual/atom-docs/blob/2.7/user-manual/administer/settings.rst?plain=1#L665

[amayita]

LGTM