Fix missing token in metadata file

Author: sebromero

content/tutorials/portenta-h7/metadata.json

@@ -19,7 +19,7 @@
      "por-ard-kvs",     
      "vs-ard-ttn",
      "por-ard-lvgl",
-     "vs-openmv-ttn"
+     "vs-openmv-ttn",
      "por-openmv-gs",
      "vs-openmv-ml",
      "ec-ard-gs"