Merge pull request #580 from stackhpc/readme-image

Reword recommendation about image

Author: bertiethorpe

README.md

@@ -31,8 +31,7 @@ It requires an OpenStack cloud, and an Ansible "deploy host" with access to that
 
 Before starting ensure that:
 - You have root access on the deploy host.
-- You can create instances using a Rocky 9 GenericCloud image (or an image based on that).
-    - **NB**: In general it is recommended to use the [latest released image](https://github.com/stackhpc/ansible-slurm-appliance/releases) which already contains the required packages. This is built and tested in StackHPC's CI.
+- You can create instances from the [latest Slurm appliance image](https://github.com/stackhpc/ansible-slurm-appliance/releases), which already contains the required packages. This is built and tested in StackHPC's CI. Although you can use a Rocky Linux 9 GenericCloud instead, it is not recommended.
 - You have an SSH keypair defined in OpenStack, with the private key available on the deploy host.
 - Created instances have access to internet (note proxies can be setup through the appliance if necessary).
 - Created instances have accurate/synchronised time (for VM instances this is usually provided by the hypervisor; if not or for bare metal instances it may be necessary to configure a time service via the appliance).