Append ECS multifields in all cases

internal/fields/validate.go

@@ -322,14 +322,14 @@ func initDependencyManagement(packageRoot string, specVersion semver.Version, im
 		}
 		logger.Debugf("Imported ECS fields definition from external schema for validation (embedded in package: %v, stack uses ecs@mappings template: %v)", packageEmbedsEcsMappings, stackSupportsEcsMapping)
 
-		// ecs@mappings adds additional multifields that are not defined anywhere. Add them here to the expected mappings.
-		// Adding them also in cases where stackSupportsEcsMapping is false so these packages can be tested with versions
-		// of the stack that support ecs@mappings.
-		ecsSchema = appendECSMappingMultifields(ecsSchema, "")
-
 		schema = ecsSchema
 	}
 
+	// ecs@mappings adds additional multifields that are not defined anywhere.
+	// Adding them in all cases so packages can be tested in versions of the stack that
+	// add the ecs@mappings component template.
+	schema = appendECSMappingMultifields(schema, "")
+
 	return fdm, schema, nil
 }