[Grenoble][chartreuse2] Update boot mode to bios

data/grid5000/sites/grenoble/clusters/chartreuse2/chartreuse2.json

 {
-  "boot_type": "uefi",
+  "boot_type": "bios",
   "created_at": "Mon, 13 Jan 2025 00:00:00 GMT",
   "exotic": false,
   "kavlan": false,

input/grid5000/sites/grenoble/clusters/chartreuse2/chartreuse2.yaml

@@ -2,7 +2,7 @@
 model: Dell PowerEdge C6320
 created_at: 2025-01-13
 kavlan: false
-boot_type: uefi
+boot_type: bios
 exotic: false
 queues:
   - admin