Feature/dotnet7 migration (#828)

* migration to .net 7

* remove temp memory database

* adapt global.json .net 7

* adapt Rich Code Navigation to .net 7

* update and clean run for .net 7

* update .net ef tool

Co-authored-by: cedri <cedri@BAS>

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "6.0.x",
+    "version": "7.0.x",
     "rollForward": "latestFeature"
   }
 }