[grenoble] Fix servan's bmc_ambient_temp_celsius metric description

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

@@ -14,7 +14,7 @@
       }
     },
     {
-      "description": "Front node ambiant temperature reported by BMC, in celsius",
+      "description": "Front node ambient temperature reported by BMC, in celsius",
       "name": "bmc_ambient_temp_celsius",
       "period": 5000,
       "scale_factor": 0.1,

input/grid5000/sites/grenoble/clusters/servan/servan_metrics.yaml

@@ -2,7 +2,7 @@
 metrics:
 
   - name: bmc_ambient_temp_celsius
-    description: Front node ambiant temperature reported by BMC, in celsius
+    description: Front node ambient temperature reported by BMC, in celsius
     period: 5000
     scale_factor: 0.1
     source: