Improve saturation alert details

When we receive alerts for saturation, it isn't usually obvious what specific instance/project/workload it refers to.

For example GCP quota limits:

We only know that it affects the environment gprd, the GCP project is not a label and we don't know what quota is actually being affected.

This MR adds the project label as a resource label to gcp_quota_limit saturation aggregations and most importantly, it updates the overall saturation function/template to include the promql_template_1 query annotation.

The annotation will propagate the promql query to the alert and make it easier to see the metrics by having a Thanos link, like the following: