update contributing guidelines for ApplySchemaCustomizations

CONTRIBUTING.md

@@ -123,7 +123,7 @@ We are migrating the resource from SDKv2 to Plugin Framework provider and hence
 2. Create a file with resource_resource-name.go and write the CRUD methods, schema for that resource. For reference, please take a look at existing resources eg: `resource_app.go`.
   - Make sure to set the user agent in all the CRUD methods.
   - In the `Metadata()`, use the method `GetDatabricksProductionName()`.
-  - In the `Schema()` method, import the appropriate struct from the `internal/service/{package}_tf` package and use the `ResourceStructToSchema` method to convert the struct to schema. Use the struct that does not have the `_SdkV2` suffix.
+  - In the `Schema()` method, import the appropriate struct from the `internal/service/{package}_tf` package and use the `ResourceStructToSchema` method to convert the struct to schema. Use the struct that does not have the `_SdkV2` suffix. The schema for the struct is automatically generated and maintained within the `ApplySchemaCustomizations` method of that struct. If you need to customize the schema further, pass in a `CustomizableSchema` to `ResourceStructToSchema` and customize the schema there. If you need to use a manually crafted struct in place of the auto-generated one, you must implement the `ApplySchemaCustomizations` method in a similar way.
 3. Create a file with `resource_resource-name_acc_test.go` and add integration tests here.
 4. Create a file with `resource_resource-name_test.go` and add unit tests here. Note: Please make sure to abstract specific method of the resource so they are unit test friendly and not testing internal part of terraform plugin framework library. You can compare the diagnostics, for example: please take a look at: `data_cluster_test.go` 
 5. Add the resource under `internal/providers/pluginfw/pluginfw.go` in `Resources()` method. Please update the list so that it stays in alphabetically sorted order.