Remove three old env variables (#2297)

* remove three old env variables IS_DATA_MODEL_SETTINGS_ENABLED IS_DEVELOPERS_SETTINGS_ENABLED FLEXIBLE_BACKEND_ENABLED

* Fix database:reset script

* Removing unused variable

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Co-authored-by: Charles Bochet <charles@twenty.com>

server/src/app.module.ts

@@ -58,8 +58,8 @@ import { ExceptionFilter } from './filters/exception.filter';
           // Extract JWT from the request
           const token = ExtractJwt.fromAuthHeaderAsBearerToken()(request.req);
 
-          // If there is no token or flexible backend is disabled, return an empty schema
-          if (!token || !environmentService.isFlexibleBackendEnabled()) {
+          // If there is no token return an empty schema
+          if (!token) {
             return new GraphQLSchema({});
           }