Try FUNCTIONS_INPROC_NET8_ENABLED

Author: DavidBoike

src/IntegrationTests.HostV4/local.settings.json

@@ -5,6 +5,8 @@
     "FUNCTIONS_WORKER_RUNTIME": "dotnet",
 
     "AzureWebJobsServiceBus": "<set your ASB connection string here>",
-    "CustomComponentValue": "Custom Component"
+    "CustomComponentValue": "Custom Component",
+
+    "FUNCTIONS_INPROC_NET8_ENABLED": 1
   }
-}
+}