Update doc schema_change_handling to optional (#370)

Author: fivetran-jovanmanojlovic

docs/resources/connector_schema_config.md

@@ -179,10 +179,10 @@ resource "fivetran_connector_schema_config" "schema" {
 ### Required
 
 - `connector_id` (String) The unique identifier for the connector within the Fivetran system.
-- `schema_change_handling` (String) The value specifying how new source data is handled.
 
 ### Optional
 
+- `schema_change_handling` (String) The value specifying how new source data is handled.
 - `schema` (Block Set, Deprecated) (see [below for nested schema](#nestedblock--schema))
 - `schemas` (Attributes Map) Map of schema configurations. (see [below for nested schema](#nestedatt--schemas))
 - `schemas_json` (String) Schema settings in Json format, following Fivetran API endpoint contract for `schemas` field (a map of schemas).