Enable logging only slow requests

[xwiz]

This enables logging of only requests which take long time to complete but not necessarily from slow queries

[taylorotwell]

Thanks for your pull request to Laravel!

Unfortunately, I'm going to delay merging this code for now. To preserve our ability to adequately maintain the framework, we need to be very careful regarding the amount of code we include.

If applicable, please consider releasing your code as a package so that the community can still take advantage of your contributions!

[xwiz]

Hi @taylorotwell greetings.., not sure what the comment means if you have a different way you'd prefer it's implemented do let me know, it's a feature I would really appreciate for quick debugging when I don't want to use external packages in moderate production environments and I'm sure it will help some others for improving application performance without having to rely on sentry and the likes.

[xwiz]

For anyone else needing this, realized this can be easily implemented, added a doc PR

laravel/docs#10623