Refactor based on recent changes as per review

Author: lresende

etc/config/metadata/component-registries/elyra-airflow-directory-preconfig.json

@@ -7,5 +7,6 @@
     "categories": ["Preloaded Airflow"],
     "paths": ["airflow"]
   },
-  "schema_name": "component-registry"
+  "schema_name": "local-directory-catalog",
+  "version": 1
 }

etc/config/metadata/component-registries/elyra-airflow-filesystem-preconfig.json

@@ -3,6 +3,7 @@
   "metadata": {
     "description": "Preloaded directory-based components that are supported by Kubeflow Pipelines",
     "runtime": "kfp",
+    "location_type": "Directory",
     "categories": ["Preloaded KFP"],
     "paths": ["kfp"]
   },