operations/mimir: Upstream Jsonnet changes from r334

[aknuds1]

What this PR does

Upstream operations/mimir Jsonnet changes from r334:

1. Don't depend on Memcached on startup
2. Set max buffered bytes in the Kafka client used by the ruler

The first is upstreamed through upgrading to latest dskit, in which the corresponding flag -dns-ignore-startup-failures's default changes to true. Therefore, we don't need to set the flag via Jsonnet any longer.

I've tested applying the PR's changes, and can see there are no differences versus our r334 cloud deployment (given that Jsonnet corresponding to change 1 is kept until the right Mimir release).

Which issue(s) this PR fixes or relates to

Fixes #

Checklist

• Tests updated.
• Documentation added.
• CHANGELOG.md updated - the order of entries should be [CHANGE], [FEATURE], [ENHANCEMENT], [BUGFIX].
• about-versioning.md updated with experimental features.

[github-actions]

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[Copilot]

Pull Request Overview

This PR applies upstream Jsonnet changes from r334 to the operations/mimir component, addressing Memcached dependency on startup and configuring the Kafka client for the ruler. Key changes include:

• Conditionally adding a Kafka producer buffered-bytes setting in the ruler configuration based on ingest storage.
• Consistently updating test files to include the new Kafka configuration parameter.
• Updating default values in documentation, help text, and config descriptors for Memcached DNS resolution.

Reviewed Changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
operations/mimir/ruler.libsonnet	Adds a conditional block to set Kafka producer-max-buffered-bytes when ingest storage is enabled.
operations/mimir-tests/*.yaml (multiple files)	Each test file now includes the new Kafka producer-max-buffered-bytes configuration parameter.
go.mod	Updates the dependency for github.com/grafana/dskit to a newer commit.
docs/sources/mimir/configure/configuration-parameters/index.md	Updates the default value for dns-ignore-startup-failures to true.
cmd/mimir/help-all.txt.tmpl	Updates help text to reflect the new default value for dns-ignore-startup-failures.
cmd/mimir/config-descriptor.json	Updates configuration descriptors to reflect the new default value for dns-ignore-startup-failures.
CHANGELOG.md	Adds entries to document the changes made in this PR.

Comments suppressed due to low confidence (1)

operations/mimir/ruler.libsonnet:34

• There is a typo in the comment ('ot he ingester' should be 'to the ingester').

// Increased from 2s to 10s in order to accommodate writing large rule results ot he ingester.