Remove thanos-staging saturation rules from global recordings

Remove thanos-staging saturation rules from global recordings

This removes the thanos-staging saturation rules from the general saturation rules that live in thanos(-staging)?-rules/autogenerated-saturation-(.*).yml files.

These saturation rules are also in the thanos(-staging)?-rules/autogenerated-thanos-self-monitoring-saturation.yml file, so there was no need to duplicate them. Especially not including the thanos-staging rules in the rules evaluated by production thanos.

It also adds the correct env and environment static-labels to the saturation resources for thanos-staging. These used to be set to thanos but should be set to thanos-staging to be in line with the SLI rules.