Add configuration option to disable cpu profiling endpoint in promtail

[Fluepke]

There is an undocumented(?) API endpoint in Promtail for CPU profiling: /debug/fgprof:

loki/clients/pkg/promtail/server/server.go

Line 106 in bd1fef0

serv.HTTP.Path("/debug/fgprof").Handler(fgprof.Handler())

Considering felixge/fgprof#12 one might want to disable this endpoint.
There should be a configuration option to disable it (or enable it if needed). There should also be documentation about this feature.

Yes, it can be done in an upstream reverse proxy, but having a configuration option would be better IMHO.

[stale]

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