test/K8sUpdates: Bump stable branch for v1.12 development
test/K8sUpdates: Bump stable branch for v1.12 development

Signed-off-by: Paul Chaignon <a027184a55211cd23e3f3094f1fdc728df5e0500@cilium.io>

cilium/cilium,michi-covalent/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium