Update oracle adapter docs (#5798)

## What are you changing in this pull request and why?

This PR updates oracle adapter docs:

  - Simpler installation and configuration using the thin driver
  - Integration with `conda` environment manager for dbt Python models
  - Oracle Specific Configuration updates

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## Checklist
- [x] Review the [Content style
guide](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/content-style-guide.md)
so my content adheres to these guidelines.
- [x] For [docs
versioning](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/single-sourcing-content.md#about-versioning),
review how to [version a whole
page](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/single-sourcing-content.md#adding-a-new-version)
and [version a block of
content](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/single-sourcing-content.md#versioning-blocks-of-content).

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Co-authored-by: Mirna Wong <[email protected]>