Draft: Adapter-specific installations of dbt

Accompanying files Bundles:

This should be reviewed and tested along with:

• files-dbt-biquery: TODO
• files-dbt-postgres: TODO
• files-dbt-redshift: TODO
• files-dbt-snowflake: files-dbt-snowflake!2 (merged)

Merge Request Checklist

• Link to an issue
• Include the proposed fix or feature
• Include and update tests for the modified code
• Include a documentation change
• Add a CHANGELOG.md entry in the Unreleased section for any user-facing changes
• Mention or assign a maintainer

Closes #3105 (closed)