Disable EF Core migrations for .NET 11 preview - use manual SQL scripts instead

.github/upgrades/scenarios/new-dotnet-version_02bc64/scenario.json

@@ -3,7 +3,7 @@
   "operationId": "02bc6448-a69d-4ff4-a0ec-0db07ec3a09a",
   "description": "Upgrade solution or project to new version of .NET",
   "startTime": "2026-03-05T22:18:32.3921759Z",
-  "lastUpdateTime": "2026-03-07T16:26:16.8032461Z",
+  "lastUpdateTime": "2026-03-07T17:48:10.3399967Z",
   "stage": "Execution",
   "properties": {},
   "folderPath": ""