Error message when using negative offset is misleading

[simonswine]

Describe the bug

The error message when using negative offset is at best misleading, as it refers to the Prometheus flag and the feature flag does not exist in Mimir

negative offset is disabled, use --enable-feature=promql-negative-offset to enable it

To Reproduce

Query using negative offset

count_over_time(up[1m] offset -10s)

Expected behavior

Adding a feature flag and display an error mentioning the correct flag -querier.at-modifier-enabled or always enable it in Mimir or mention that negative offsets are not supported in Mimir

[pstibrany]

Negative offsets may be enabled by default (without possibility to disable them) in PromQL soon: prometheus/prometheus#10121

[pstibrany]

Negative offsets may be enabled by default (without possibility to disable them) in PromQL soon: prometheus/prometheus#10121

Oh, I misread the PR. It actually doesn't remove the option to enable/disable negative offsets, nor does it make them enabled by default. It just removes "experimental" designation.