s3: apply grammar suggestion from @jar-b

Co-authored-by: Jared Baker <[email protected]>

website/docs/language/backend/s3.mdx

@@ -43,7 +43,7 @@ Using the example above, the state for the workspace `development` would be stor
 
 State locking is an opt-in feature of the S3 backend.
 
-Locking can be enabled via an S3 or DynamoDB. However, **DynamoDB-based locking is deprecated** and will be removed in a future minor version. To support migration from older versions of Terraform that only support DynamoDB-based locking, the S3 and DynamoDB arguments can be configured simultaneously.
+Locking can be enabled via S3 or DynamoDB. However, **DynamoDB-based locking is deprecated** and will be removed in a future minor version. To support migration from older versions of Terraform that only support DynamoDB-based locking, the S3 and DynamoDB arguments can be configured simultaneously.
 
 #### Enabling S3 State Locking