Update data test descriptions (#6307)

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

Generic Test descriptions can now be documented

Closes #6293

## Checklist
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guide](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/content-style-guide.md)
so my content adheres to these guidelines.
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have versioned it according to the [version a whole
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and/or [version a block of
content](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/single-sourcing-content.md#versioning-blocks-of-content)
guidelines.
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that needs to happen before this PR is merged, such as "needs technical
review" or "change base branch."
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<!-- vercel-deployment-preview -->
---
🚀 Deployment available! Here are the direct links to the updated files:


-
https://docs-getdbt-com-git-test-description-dbt-labs.vercel.app/reference/resource-properties/description

<!-- end-vercel-deployment-preview -->

---------

Co-authored-by: Mirna Wong <89008547+mirnawong1@users.noreply.github.com>

website/docs/reference/resource-properties/description.md

@@ -13,7 +13,7 @@ description: "This guide explains how to use the description key to add YAML des
     { label: 'Snapshots', value: 'snapshots', },
     { label: 'Analyses', value: 'analyses', },
     { label: 'Macros', value: 'macros', },
-    { label: 'Singular data tests', value: 'singular_data_tests', },
+    { label: 'Data tests', value: 'data_tests', },
   ]
 }>
 <TabItem value="models">
@@ -146,17 +146,17 @@ macros:
 
 </TabItem>
 
-<TabItem value="singular_data_tests">
+<TabItem value="data_tests">
 
 <VersionBlock firstVersion="1.9">
 
-<File name='tests/singular/schema.yml'>
+<File name='tests/schema.yml'>
 
 ```yml
 version: 2
 
 data_tests:
-  - name: singular_data_test_name
+  - name: data_test_name
     description: markdown_string
 
 ```
@@ -167,13 +167,12 @@ data_tests:
 
 <VersionBlock lastVersion="1.8">
 
-The `description` property is available for singular data tests beginning in dbt v1.9.
+The `description` property is available for generic and singular data tests beginning in dbt v1.9.
 
 </VersionBlock>
 
 </TabItem>
 
-
 </Tabs>
 
 ## Definition