Temporarily disable storprep for a couple of hours

Change-Id: Iceb541856ac84c1626d5714529317e08d52c0c34
diff --git a/playbooks/sp-init.yaml b/playbooks/sp-init.yaml
index 05914f8..4eab4ad 100644
--- a/playbooks/sp-init.yaml
+++ b/playbooks/sp-init.yaml
@@ -14,7 +14,7 @@
 
     - name: ctrl-sp-run-storprep
       shell:
-        cmd: sh '{{ storprep_filename }}' -- -n lab-charmed-testing-storage -s lab-vlan400 -- {{ host_id }}
+        cmd: echo sh '{{ storprep_filename }}' -- -n lab-charmed-testing-storage -s lab-vlan400 -- {{ host_id }}
 
     - name: ctrl-sp-rm-storprep
       shell: