[4/n]: migrate the RESTAPI GET /rest/* to use TwentyORM directly (#10372)

# This PR

- Addressing #3644
- Migrates the `findOne` and the `findMany` Rest API to use TwentyORM
directly
- Adds integration tests to the migrated methods

---------

Co-authored-by: prastoin <paul@twenty.com>
Co-authored-by: martmull <martmull@hotmail.fr>

packages/twenty-server/src/app.module.ts

@@ -37,6 +37,7 @@ const MIGRATED_REST_METHODS = [
   RequestMethod.POST,
   RequestMethod.PATCH,
   RequestMethod.PUT,
+  RequestMethod.GET,
 ];
 
 @Module({