Update BIOS and Release Date of Grisou Cluster

Update BIOS and Release Date of Grisou Cluster on input/grid5000/sites/nancy/clusters/grisou/nodes/*.yaml

data/grid5000/sites/nancy/clusters/grisou/nodes/grisou-1.json

@@ -6,9 +6,9 @@
     "platform_type": "x86_64"
   },
   "bios": {
-    "release_date": "005/17/2018",
+    "release_date": "12/04/2018",
     "vendor": "Dell Inc.",
-    "version": "2.8.0"
+    "version": "2.9.1"
   },
   "chassis": {
     "manufacturer": "Dell Inc.",