Add defer image to docs (#5904)

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

Adding a defer diagram image to docs. Working together with @mirnawong1.

## 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.
- [ ] 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).
- [ ] Add a checklist item for anything that needs to happen before this
PR is merged, such as "needs technical review" or "change base branch."

---------

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

website/docs/docs/cloud/about-cloud-develop-defer.md

@@ -11,6 +11,8 @@ pagination_next: "docs/cloud/cloud-cli-installation"
 
 Both the dbt Cloud IDE and the dbt Cloud CLI enable users to natively defer to production metadata directly in their development workflows. 
 
+<Lightbox src src="/img/docs/reference/defer-diagram.png" width="50%" title="Use 'defer' to modify end-of-pipeline models by pointing to production models, instead of running everything upstream." />
+
 By default, dbt follows these rules:
 
 - dbt uses the production locations of parent models to resolve `{{ ref() }}` functions, based on metadata from the production environment.

website/docs/reference/node-selection/defer.md

@@ -4,6 +4,8 @@ title: "Defer"
 
 Defer is a powerful feature that makes it possible to run a subset of models or tests in a [sandbox environment](/docs/environments-in-dbt) without having to first build their upstream parents. This can save time and computational resources when you want to test a small number of models in a large project.
 
+<Lightbox src src="/img/docs/reference/defer-diagram.png" width="50%" title="Use 'defer' to modify end-of-pipeline models by pointing to production models, instead of running everything upstream." />
+
 Defer requires that a manifest from a previous dbt invocation be passed to the `--state` flag or env var. Together with the `state:` selection method, these features enable "Slim CI". Read more about [state](/reference/node-selection/syntax#about-node-selection).
 
 An alternative command that accomplishes similar functionality for different use cases is `dbt clone` - see the docs for [clone](/reference/commands/clone#when-to-use-dbt-clone-instead-of-deferral) for more information.