Merge pull request #1076 from lsst-it/renovate/mimir-distributed-5.x

Update Helm release mimir-distributed to v5.8.0

Author: jhoblitt

fleet/lib/mimir/fleet.yaml

@@ -9,7 +9,7 @@ helm:
   chart: &chart mimir-distributed
   releaseName: *chart
   repo: https://grafana.github.io/helm-charts
-  version: 5.7.0
+  version: 5.8.0
   timeoutSeconds: 600
   waitForJobs: true
   valuesFiles: