Instrumentation of NestJS functional middleware

https://docs.nestjs.com/middleware#functional-middleware

Currently we have auto instrumentation for class based middleware. To do that we hook into the `@Injectable` decorator and patch the implemented `use` method on the class. However, nest also allows to add middlewares that are vanilla functions via `app.use` or the `MiddlewareConsumer`. These functional middlewares can be manually decorated with `SentryTraced` to get instrumentation but it would be better to have them auto-instumented.