[Doc] Update RA Core EE documentation

Author: React-Admin CI

docs_headless/src/content/docs/AutoPersistInStoreBase.md

@@ -16,7 +16,7 @@ The temporary form data is only saved when the user navigates away from the page
 
 Saved data is not sent to the server. It is only persisted using the [store](https://marmelab.com/ra-core/store/) and is removed when the user logs out.
 
-This feature requires a valid is an [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
+This feature requires a valid [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
 
 ### Usage
 

docs_headless/src/content/docs/AutoSaveBase.md

@@ -9,7 +9,7 @@ A component that enables autosaving of the form. It's ideal for long data entry
   Your browser does not support the video tag.
 </video>
 
-This feature requires a valid is an [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
+This feature requires a valid [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
 
 ## Usage
 

docs_headless/src/content/docs/BulkUpdateFormBase.md

@@ -9,7 +9,7 @@ This component can be used to create forms that update multiple records at once.
   Your browser does not support the video tag.
 </video>
 
-This feature requires a valid is an [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
+This feature requires a valid [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
 
 ## Usage
 

docs_headless/src/content/docs/useAutoPersistInStore.md

@@ -16,7 +16,7 @@ The temporary form data is only saved when the user navigates away from the page
 
 Saved data is not sent to the server. It is only persisted using the [store](https://marmelab.com/ra-core/store/) and is removed when the user logs out.
 
-This feature requires a valid is an [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
+This feature requires a valid [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
 
 ### Usage
 

docs_headless/src/content/docs/useAutoSave.md

@@ -4,7 +4,7 @@ title: "useAutoSave"
 
 A hook that automatically saves the form at a regular interval. It works for the `pessimistic` and `optimistic` [`mutationMode`](https://marmelab.com/ra-core/editbase/#mutationmode) but not for the `undoable`.
 
-This feature requires a valid is an [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
+This feature requires a valid [Enterprise Edition](https://marmelab.com/ra-enterprise/) subscription.
 
 ## Usage