Make Azure OS disk type configurable and default to a cheaper type (#14533)

* add azure option for osDiskType

* azure: change default image to minimal ubuntu

config.cfg

@@ -165,10 +165,15 @@ SSH_keys:
 cloud_providers:
   azure:
     size: Standard_B1S
+    osDisk:
+      # The storage account type to use for the OS disk. Possible values:
+      # 'Standard_LRS', 'Premium_LRS', 'StandardSSD_LRS', 'UltraSSD_LRS',
+      # 'Premium_ZRS', 'StandardSSD_ZRS', 'PremiumV2_LRS'.
+      type: Standard_LRS
     image:
       publisher: Canonical
-      offer: 0001-com-ubuntu-server-focal-daily
-      sku: 20_04-daily-lts
+      offer: 0001-com-ubuntu-minimal-focal-daily
+      sku: minimal-20_04-daily-lts
       version: latest
   digitalocean:
     size: s-1vcpu-1gb

roles/cloud-azure/files/deployment.json

@@ -23,6 +23,9 @@
     "imageReferenceVersion": {
       "type": "string"
     },
+    "osDiskType": {
+      "type": "string"
+    },
     "SshPort": {
       "type": "int"
     },
@@ -197,7 +200,10 @@
             "version": "[parameters('imageReferenceVersion')]"
           },
           "osDisk": {
-            "createOption": "FromImage"
+            "createOption": "FromImage",
+            "managedDisk": {
+              "storageAccountType": "[parameters('osDiskType')]"
+            }
           }
         },
         "networkProfile": {

roles/cloud-azure/tasks/main.yml

@@ -37,6 +37,8 @@
         value: "{{ cloud_providers.azure.image.sku }}"
       imageReferenceVersion:
         value: "{{ cloud_providers.azure.image.version }}"
+      osDiskType:
+        value: "{{ cloud_providers.azure.osDisk.type }}"
       SshPort:
         value: "{{ ssh_port }}"
       UserData: