fix: adds deprecation warning on JSON Schema Draft 3 usage

Author: artem-zakharchenko

lib/validators/json-schema-legacy.js

@@ -76,6 +76,10 @@ class JsonSchemaLegacy extends JsonSchemaValidator {
 
     switch (this.jsonSchemaVersion) {
       case 'draftV3':
+        // eslint-disable-line no-console
+        console.warn(
+          'DEPRECATED: JSON Schema Draft V3 is deprecated. Please use a newer version of JSON Schema (Draft V4-7).'
+        );
         return this.validateUsingAmanda(parsedData);
       case 'draftV4':
         return this.validateUsingTV4(parsedData);