Fix network interfaces metadata data type

Related-Prod: PRODX-3456
Change-Id: I68c2c10f38365e2c168995e48f948b8d77fade94
diff --git a/de/heat-templates/scripts/instance_boot.sh b/de/heat-templates/scripts/instance_boot.sh
index 7a7eb76..473938f 100644
--- a/de/heat-templates/scripts/instance_boot.sh
+++ b/de/heat-templates/scripts/instance_boot.sh
@@ -565,9 +565,9 @@
 
     cat << EOF > ${if_metadata_file}
 ${if_name}:
-  pci_id: ${pci_id}
-  ip_addr: ${ip}
-  mac: ${mac}
+  pci_id: "${pci_id}"
+  ip_addr: "${ip}"
+  mac: "${mac}"
 EOF
 
     HW_METADATA=$(echo ${HW_METADATA} | jq -cr ". += {\"interfaces\": {\"$(hostname)\": \"$(base64 -w 0 ${if_metadata_file})\"}}")