Update screenshots in AtoM docs to show the BS5 variants instead of BS2

Update all screenshots that show BS2 elements with the BS5 version

List of screenshots sections:

### User Manual

- [ ] [Access content](https://github.com/artefactual/atom-docs/tree/2.7/user-manual/access-content)
- [ ] [Add/Edit content](https://github.com/artefactual/atom-docs/tree/2.7/user-manual/add-edit-content)
- [ ] [Administer](https://github.com/artefactual/atom-docs/tree/2.7/user-manual/administer)
- [ ] [Data Templates](https://github.com/artefactual/atom-docs/tree/2.7/user-manual/data-templates)
- [x] [Getting Started](https://github.com/artefactual/atom-docs/tree/2.7/user-manual/getting-started)
- [ ] [Import/export](https://github.com/artefactual/atom-docs/tree/2.7/user-manual/import-export)
- [ ] [Reports printing](https://github.com/artefactual/atom-docs/tree/2.7/user-manual/reports-printing)
- [ ] [Translate](https://github.com/artefactual/atom-docs/tree/2.7/user-manual/translate)

### Developer Manual

- [ ] [API](https://github.com/artefactual/atom-docs/tree/2.7/dev-manual/api)

### Admin Manual

- [ ] [Customization](https://github.com/artefactual/atom-docs/tree/2.7/admin-manual/customization)
- [ ] [Maintenance](https://github.com/artefactual/atom-docs/tree/2.7/admin-manual/maintenance)

Review the listed User Manual, Developer Manual, and Admin Manual sections in the atom-docs 2.7 tree, starting with the unchecked links and comparing their screenshots with the BS5 interface. Replace screenshots that show BS2 elements, verify the resulting images in each section, and leave Getting Started unchanged because it is already marked complete.

Written by the indexing model from the issue text.