do not allow additional properties in config

resources/config_schema.json

@@ -3,6 +3,7 @@
     "title": "Configuration schema",
     "required": ["samples", "output_dir", "log_dir", "kallisto_indexes", "salmon_indexes", "star_indexes", "alfa_indexes"],
     "type": "object",
+    "additionalProperties": false,
     "properties": {
       "samples": {
         "type": "string",