cirrus: Use SSD cluster for speedup

.cirrus.yml

@@ -28,7 +28,6 @@ global_task_template: &GLOBAL_TASK_TEMPLATE
     # Each project has 16 CPU in total, assign 2 to each container, so that 8 tasks run in parallel
     cpu: 2
     memory: 8G  # Set to 8GB to avoid OOM. https://cirrus-ci.org/guide/linux/#linux-containers
-    kvm: true  # Use kvm to avoid spurious CI failures in the default virtualization cluster, see https://github.com/bitcoin/bitcoin/issues/20093
   ccache_cache:
     folder: "/tmp/ccache_dir"
   depends_built_cache: