Docs: scrape_classic_histograms renamed to always_scrape_classic_histograms in Prometheus 3.0

[krajorama]

Is your documentation request related to a feature? If so, which one?

Due to prometheus/prometheus#15178 we'll have to update the documentation

mimir/docs/sources/mimir/send/native-histograms/_index.md

Line 114 in b2c35f5

scrape_classic_histograms: true

mimir/docs/sources/mimir/send/native-histograms/_index.md

Line 156 in b2c35f5

scrape_classic_histograms = true

maybe other places as well?

Describe the solution that you’d like or the expected outcome

I think we should document the 3.0 way as primary and just mention 2.x way, wdyt?

[tacole02]

Thanks for creating this issue, @krajorama ! What timeline do you have in mind for completion?

[tacole02]

TImeline: ~ mid November, 2024