Clean up deprecated configuaration options already listed in the documentation.

[JStickler]

There are 32 configuration options already marked as deprecated in the documentation.

https://grafana.com/docs/loki/latest/configure/

[ivaresarthak-cloud]

Hi, I'd like to work on this issue. I have hands-on experience with Grafana and Prometheus from a CI/CD pipeline monitoring project. I'll start by going through the deprecated options listed at the docs link and clean them up. Could you please assign this to me?