Add a slogAdapter converting go-kit/log to slog

[SungJin1212]

The Prometheus v3.0.0 uses a slog instead of the go-kit/log. In other words, the passed log parameter is changed to slog.
To upgrade Prometheus v3.0.0, we should pass slog instead of go-kit/log.

So, it might be good to implement a slogAdapter which converts go-kit/log to slog.

[yeya24]

FYI we probably need to update the common library to support slog there. https://github.com/cortexproject/weaveworks-common/tree/master/logging

We can try the adapter approach https://github.com/tjhop/slog-gokit first and see if it is good enough.

[CharlieTLe]

Might be a good opportunity to see if we can use OpenTelemetry-go for logging here as the api and use slog as the sdk. Benefits include standardization of logging and exemplar support with traces.