Hyperlinks for snapshot configs for property YAML files (#6213)

[Preview](https://docs-getdbt-com-git-dbeatty10-patch-2-dbt-labs.vercel.app/reference/snapshot-configs#snapshot-specific-configurations)

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

I accidentally overlooked adding hyperlinks during the PR that added
this example, so adding them now!

## Checklist
- [x] I have reviewed 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.

website/docs/reference/snapshot-configs.md

@@ -94,12 +94,12 @@ snapshots:
 snapshots:
   - name: <string>
     config:
-      database: <string>
-      schema: <string>
-      unique_key: <column_name_or_expression>
-      strategy: timestamp | check
-      updated_at: <column_name>
-      check_cols: [<column_name>] | all
+      [database](/reference/resource-configs/database): <string>
+      [schema](/reference/resource-configs/schema): <string>
+      [unique_key](/reference/resource-configs/unique_key): <column_name_or_expression>
+      [strategy](/reference/resource-configs/strategy): timestamp | check
+      [updated_at](/reference/resource-configs/updated_at): <column_name>
+      [check_cols](/reference/resource-configs/check_cols): [<column_name>] | all
 
 ```
 </File>