Build magnum images from fork

Author: mnasiadka

etc/kayobe/kolla.yml

@@ -140,6 +140,10 @@ kolla_sources:
     type: git
     location: https://github.com/stackhpc/stackhpc-inspector-plugins.git
     reference: 1.3.0
+  magnum-base:
+    type: git
+    location: https://github.com/stackhpc/magnum.git
+    reference: 2025_1_speed_improvements
   neutron-base-plugin-networking-generic-switch:
     type: git
     location: https://github.com/stackhpc/networking-generic-switch.git