[ENT-1039] add link to the new VCS docs on the about-privatelink page (…

…#4579)

## What are you changing in this pull request and why?
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Took a look at the PrivateLink docs and noticed the `about-privatelink`
page was missing a link to the new VCS docs.

## Checklist
<!--
Uncomment if you're publishing docs for a prerelease version of dbt
(delete if not applicable):
- [ ] Add versioning components, as described in [Versioning
Docs](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/single-sourcing-content.md#versioning-entire-pages)
- [ ] Add a note to the prerelease version [Migration
Guide](https://github.com/dbt-labs/docs.getdbt.com/tree/current/website/docs/docs/dbt-versions/core-upgrade)
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- [ ] 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."

Adding new pages (delete if not applicable):
- [ ] Add page to `website/sidebars.js`
- [ ] Provide a unique filename for the new page

Removing or renaming existing pages (delete if not applicable):
- [ ] Remove page from `website/sidebars.js`
- [ ] Add an entry `website/static/_redirects`
- [ ] Run link testing locally with `npm run build` to update the links
that point to the deleted page

website/docs/docs/cloud/secure/about-privatelink.md

@@ -23,3 +23,4 @@ dbt Cloud supports the following data platforms for use with the PrivateLink fea
 - [Databricks](/docs/cloud/secure/databricks-privatelink)
 - [Redshift](/docs/cloud/secure/redshift-privatelink)
 - [Postgres](/docs/cloud/secure/postgres-privatelink)
+- [VCS](/docs/cloud/secure/vcs-privatelink)