Upgrade Storpool driver to Caracal

When we released, the Bobcat was the latest driver and now
Caracal is the latest available driver.

Change-Id: I3e2988dc79097645bab5d955a899fe64f3984023
diff --git a/images/nova/Dockerfile b/images/nova/Dockerfile
index eac8737..30517aa 100644
--- a/images/nova/Dockerfile
+++ b/images/nova/Dockerfile
@@ -21,7 +21,7 @@
         storpool.spopenstack
 EOF
 ADD --chmod=644 \
-    https://github.com/storpool/storpool-openstack-integration/raw/master/drivers/os_brick/openstack/bobcat/storpool.py \
+    https://github.com/storpool/storpool-openstack-integration/raw/master/drivers/os_brick/openstack/caracal/storpool.py \
     /var/lib/openstack/lib/python3.10/site-packages/os_brick/initiator/connectors/storpool.py
 
 FROM openstack-python-runtime