[input_loader] Change the regex to support cluster with number in the name

On a changé la regex pour qu'il supporte le traitement des clusters avec un chiffre devant leur nom et qui ont plusieurs interfaces commme chiconade1

data/grid5000/sites/lille/clusters/chiconade1/nodes/chiconade1-1.json

@@ -90,8 +90,8 @@
       "rate": 25000000000,
       "sriov": false,
       "sriov_totalvfs": 0,
-      "switch": null,
-      "switch_port": null,
+      "switch": "sw-chiclet-1",
+      "switch_port": "Ethernet1/33",
       "vendor": "Broadcom Inc. and subsidiaries"
     },
     {
@@ -113,8 +113,8 @@
       "rate": 25000000000,
       "sriov": false,
       "sriov_totalvfs": 0,
-      "switch": null,
-      "switch_port": null,
+      "switch": "sw-chiclet-1",
+      "switch_port": "Ethernet1/34",
       "vendor": "Broadcom Inc. and subsidiaries"
     },
     {