[9.1] (backport #11481) fix: spec invalid rendered values "null"

[mergify]

What does this PR do?

• Modifies the kube-stack configurations to prevent "null" values in the Helm v4.
• Bumps Helm v4 and its dependencies.

Why is it important?

Fixes the deployment with Helm 4, error message:

Error: Instrumentation.opentelemetry.io "elastic-instrumentation" is invalid: spec.env: Invalid value: "null": spec.env in body must be of type array: "null"
OpenTelemetryCollector.opentelemetry.io "opentelemetry-kube-stack-gateway" is invalid: [spec.config.service.pipelines.metrics/aggregated-otel-metrics.processors: Invalid value: "null": spec.config.service.pipelines.metrics/aggregated-otel-metrics.processors in body must be of type array: "null", <nil>: Invalid value: "null": some validation rules were not checked because the object was invalid; correct the existing errors to complete validation]

Checklist

• I have read and understood the pull request guidelines of this project.
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in ./changelog/fragments using the changelog tool
• I have added an integration test or an E2E test

Disruptive User Impact

How to test this PR locally

Related issues

Questions to ask yourself

• How are we going to support this in production?
• How are we going to measure its adoption?
• How are we going to debug this?
• What are the metrics I should take care of?
• ...

---

This is an automatic backport of pull request #11481 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 6a7cd38 has failed:

On branch mergify/bp/9.1/pr-11481
Your branch is up to date with 'origin/9.1'.

You are currently cherry-picking commit 6a7cd38f5.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	new file:   changelog/fragments/1764348725-fix_templates_for_helm_4.yaml
	modified:   deploy/helm/edot-collector/kube-stack/managed_otlp/logs-values.yaml

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   deploy/helm/edot-collector/kube-stack/managed_otlp/values.yaml
	both modified:   deploy/helm/edot-collector/kube-stack/values.yaml

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[elasticmachine]

⏳ Build in-progress, with failures

• Buildkite Build
• Commit: 373265e

Failed CI Steps

• Unit tests - Ubuntu 22.04 with requirefips build tag
• Unit tests - Ubuntu 22.04 with requirefips build tag

History

• 💔 Build #31924 failed 5b22621

cc @rogercoll