[FIX] Update README links to user guide in docs

[alyssadai]

• Related to [REF] Create custom paths for user guide and data model pages, refactor section on local_nb_nodes.json documentation#242

Changes proposed in this pull request:

• Removed outdated link to docs in setup script, since this script is no longer exposed to the user (and we don't advise using the manual graph setup steps that are documented)

Checklist

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• PR has an interpretable title with a prefix ([ENH], [FIX], [REF], [TST], [CI], [MNT], [INF], [MODEL], [DOC]) (see our Contributing Guidelines for more info)
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• PR links to GitHub issue with mention Closes #XXXX
• Tests pass
• Checks pass

For new features:

• Tests have been added

For bug fixes:

• There is at least one test that would fail under the original bug conditions.

[surchs]

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