CI: Update aio VM flavor, network and subnet for Leafcloud

Author: markgoddard

.github/workflows/stackhpc-all-in-one.yml

@@ -38,15 +38,15 @@ on:
       vm_flavor:
         description: Flavor for the all-in-one VM
         type: string
-        default: general.v1.medium
+        default: en1.medium
       vm_network:
         description: Network for the all-in-one VM
         type: string
-        default: stackhpc-release
+        default: stackhpc-ci
       vm_subnet:
         description: Subnet for the all-in-one VM
         type: string
-        default: stackhpc-release-subnet
+        default: stackhpc-ci
       OS_CLOUD:
         description: Name of cloud in clouds.yaml
         type: string