[mimir-distributed-release-5.7] Update Mimir and GEM image versions (g…

…rafana#10962)

* [mimir-distributed-5.7] Update Mimir image version for 2.16 RC

Update Mimir to 2.16.0-rc.0 image versions and update the chart
version to 5.7.0-rc.0. Note that the GEM RC version doesn't exist
yet and so hasn't been updated.

Part of grafana#10917

Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>

* Release notes for 5.7

Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>

* Increment documentation version

Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>

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Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>

Update mimir-distributed chart to 5.7.0-weekly.334 (grafana#10926)

Co-authored-by: grafanabot <grafanabot@grafana.com>

v2.16.0-rc.0

v2.15.1

Update mimir-distributed chart to 5.7.0-weekly.333 (grafana#10846)

Co-authored-by: grafanabot <grafanabot@grafana.com>

Update mimir-distributed chart to 5.7.0-weekly.332 (grafana#10791)

Co-authored-by: grafanabot <grafanabot@grafana.com>

Update mimir-distributed chart to 5.7.0-weekly.331 (grafana#10726)

Co-authored-by: grafanabot <grafanabot@grafana.com>

Update mimir-distributed chart to 5.7.0-weekly.330 (grafana#10670)

Co-authored-by: grafanabot <grafanabot@grafana.com>

Update mimir-distributed chart to 5.7.0-weekly.329 (grafana#10619)

Co-authored-by: grafanabot <grafanabot@grafana.com>

Update mimir-distributed chart to 5.7.0-weekly.328 (grafana#10566)

Co-authored-by: grafanabot <grafanabot@grafana.com>