6347 Cache the number of each component type assigned to devices/VMs (#12632)

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Co-authored-by: Jeremy Stretch <jstretch@netboxlabs.com>

netbox/virtualization/apps.py

@@ -6,3 +6,8 @@ class VirtualizationConfig(AppConfig):
 
     def ready(self):
         from . import search
+        from .models import VirtualMachine
+        from utilities.counters import connect_counters
+
+        # Register counters
+        connect_counters(VirtualMachine)