[Doc] Add missing backticks for default empty value example

Author: adguernier

docs/AutocompleteArrayInput.md

@@ -254,7 +254,7 @@ You can override this value with the `emptyValue` prop.
 <AutocompleteArrayInput source="roles" choices={choices} emptyValue={0} />
 ```
 
-**Tip**: While you can set `emptyValue` to a non-string value (e.g. `0`), you cannot use `null` or `undefined`, as it would turn the `<AutocompleteArrayInput>` into an [uncontrolled component](https://react.dev/learn/sharing-state-between-components#controlled-and-uncontrolled-components). If you need the empty choice to be stored as `null` or `undefined`, use [the `parse` prop](./Inputs.md#parse) to convert the default empty value ('') to `null` or `undefined`, or use [the `sanitizeEmptyValues` prop](./SimpleForm.md#sanitizeemptyvalues) on the Form component. 
+**Tip**: While you can set `emptyValue` to a non-string value (e.g. `0`), you cannot use `null` or `undefined`, as it would turn the `<AutocompleteArrayInput>` into an [uncontrolled component](https://react.dev/learn/sharing-state-between-components#controlled-and-uncontrolled-components). If you need the empty choice to be stored as `null` or `undefined`, use [the `parse` prop](./Inputs.md#parse) to convert the default empty value (`''`) to `null` or `undefined`, or use [the `sanitizeEmptyValues` prop](./SimpleForm.md#sanitizeemptyvalues) on the Form component. 
 
 ## `filterToQuery`