DEVDOCS-5320: [update] update link for template_files (#802)

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# [DEVDOCS-5320]


## What changed?
Update link for a list of accepted `template_file` values

## Release notes draft

Bug Fix: Corrected link
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language. Don't be too technical. Explain how the change will benefit
the merchant and link to the feature.

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* The newly-released [X feature] is now available to use. Now, you’ll be
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* We're happy to announce [X feature], which can help you [perform Y
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* [X feature] helps you to create [Y response] using the [Z query
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* Fixed a bug in the [X endpoint]. Now the [Y field] will appear when
you click [Z option]. -->
* 

## Anything else?
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ping {names}


[DEVDOCS-5320]:
https://bigcommercecloud.atlassian.net/browse/DEVDOCS-5320?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

docs/storefront/widgets/guide/graphql-templates.mdx

@@ -302,7 +302,7 @@ Accept: application/json
 }
 ```
 
-For a list of accepted `template_file` values, see the [Create a placement](/docs/rest-content/widgets/widget#create-a-widget) reference.
+For a list of accepted `template_file` values, see [Placements](/docs/storefront/widgets#placements).
 
 To determine the value of the `region` property, send a request to the [Get a list of theme regions](/docs/rest-content/widgets/regions#get-theme-regions) endpoint and pass the desired `template_file` value as a query parameter.