Chore: Using schemaId: "auto" instead of "id"

This retains compatibility with json schema draft-04 as well as draft-06 and draft-07. Previous setting unintentionally restricted compatibility to draft-04.

lib/util/ajv.js

@@ -20,7 +20,7 @@ const ajv = new Ajv({
     validateSchema: false,
     missingRefs: "ignore",
     verbose: true,
-    schemaId: "id"
+    schemaId: "auto"
 });
 
 ajv.addMetaSchema(metaSchema);