CI: Make rocky9 VM jobs non-voting

These jobs are broken due to a missing cirros image from cache [1].

[1] https://review.opendev.org/c/opendev/zuul-providers/+/953908

Change-Id: Ic19aee58748e088e6d68a476ed82e48e5b186822
Signed-off-by: Pierre Riteau <[email protected]>
(cherry picked from commit b67587e)

Author: priteau

zuul.d/project.yaml

@@ -33,11 +33,14 @@
         - kayobe-seed-upgrade-rocky9
         - kayobe-seed-upgrade-ubuntu-noble
         - kayobe-seed-upgrade-slurp-rocky9
-        - kayobe-seed-vm-rocky9
-        - kayobe-seed-vm-rocky9-efi
+        - kayobe-seed-vm-rocky9:
+            voting: false
+        - kayobe-seed-vm-rocky9-efi:
+            voting: false
         - kayobe-seed-vm-ubuntu-noble
         - kayobe-seed-vm-ubuntu-noble-efi
-        - kayobe-infra-vm-rocky9
+        - kayobe-infra-vm-rocky9:
+            voting: false
         - kayobe-infra-vm-ubuntu-noble
     gate:
       jobs:
@@ -65,9 +68,7 @@
         - kayobe-seed-upgrade-rocky9
         - kayobe-seed-upgrade-ubuntu-noble
         - kayobe-seed-upgrade-slurp-rocky9
-        - kayobe-seed-vm-rocky9
         - kayobe-seed-vm-ubuntu-noble
-        - kayobe-infra-vm-rocky9
         - kayobe-infra-vm-ubuntu-noble
 
     experimental: