change base image to fedora core

.github/workflows/runner_recreate.yml

@@ -23,7 +23,7 @@ on:
     types: [ labeled ]
 
 env:
-  RUNNER_BASE_IMAGE: "Fedora 36"
+  RUNNER_BASE_IMAGE: "Fedora CoreOS 40"
   INSTANCE_NAME: "ci_runner"
   OS_AUTH_URL: "https://openstack.osuosl.org:5000/v3"
   OS_PROJECT_NAME: "godon"
@@ -85,7 +85,7 @@ jobs:
                    -i "$(cat ./instance_address),"
                    --private-key ./access_key_file
                    --ssh-extra-args="-o StrictHostKeyChecking=accept-new"
-                   -u fedora
+                   -u core
                    --become
                    -T 120
                    -m raw -a "hostnamectl set-hostname ci_runner;