Add docs for zone cache variants

[maleblond]

Follow-up of #1444

I'm unsure if that's the proper way of updating the docs shown at https://registry.terraform.io/providers/cloudflare/cloudflare/latest/docs . I'm also unsure about how to test those changes

[github-actions]

Oops! It looks like no changelog entry is attached to this PR. Please include a release note as described in https://github.com/cloudflare/terraform-provider-cloudflare/blob/master/docs/changelog-process.md.

Example:

```release-note:TYPE
Release note
```

If you do not require a release note to be included, please add the workflow/skip-changelog-entry label.

[jacobbednarz]

I'm also unsure about how to test those changes

make website will generate the files locally for you to view.

[maleblond]

I'm also unsure about how to test those changes

make website will generate the files locally for you to view.

make website fails:

ln -sf ../../../../ext/providers/cloudflare/website/docs <GOPATH>/src/github.com/hashicorp/terraform-website/content/source/docs/providers/cloudflare
ln: <GOPATH>/src/github.com/hashicorp/terraform-website/content/source/docs/providers/cloudflare: No such file or directory

It appears https://github.com/hashicorp/terraform-website/tree/master/content no longer has a source folder

[jacobbednarz]

It appears https://github.com/hashicorp/terraform-website/tree/master/content no longer has a source folder

😢 i must still have it locally somewhere. there is also https://registry.terraform.io/tools/doc-preview but that only works for the body of the content and not things like the sidebar.

[jacobbednarz]

cheers for following up with this one!