feat(opensearch): add data_nodes_count attribute to OpenSearchDomain

prowler/providers/aws/services/opensearch/opensearch_service.py

@@ -141,6 +141,11 @@ class OpenSearchService(AWSService):
                     .get("ClusterConfig", {})
                     .get("DedicatedMasterCount", 0)
                 )
+                domain.data_nodes_count = (
+                    describe_domain["DomainStatus"]
+                    .get("ClusterConfig", {})
+                    .get("InstanceCount", 0)
+                )
         except Exception as error:
             logger.error(
                 f"{regional_client.region} -- {error.__class__.__name__}[{error.__traceback__.tb_lineno}]: {error}"
@@ -185,4 +190,5 @@ class OpenSearchDomain(BaseModel):
     advanced_settings_enabled: bool = None
     dedicated_master_enabled: Optional[bool]
     dedicated_master_count: Optional[int]
+    data_nodes_count: Optional[int]
     tags: Optional[list] = []