Update metric expiry and cardinality docs to mention sidecar.istio.io/statsEvictionInterval and Telemetry resource

[ringerc]

Description

• Update the FAQ for metric expiry to mention sidecar.istio.io/statsEvictionInterval now that support for metric expiry was added by telemetry: add bootstrap annotations for stats flush and eviction istio#57736
• Mention the Telemetry resource's features for overriding metrics and dimensions in the FAQ for metric cardinality
• Link to the Telemetry resource and the docs for customising metrics in the reference docs for standard labels
• Warn that dropping labels scrape-side in Prometheus will have undesired results

Reviewers

• Ambient
• Docs
• Installation
• Networking
• Performance and Scalability
• Extensions and Telemetry
• Security
• Test and Release
• User Experience
• Developer Infrastructure
• Localization/Translation

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[istio-testing]

Hi @ringerc. Thanks for your PR.

I'm waiting for a github.com member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[Arhell]

/ok-to-test

[Ajay-singh1]

The tests are failing you need to run make lint to fix the linting errors.

[ringerc]

@Ajay-singh1 Fixed, thanks

[zirain]

Thanks for adding this.

[dhawton]

We do not do strikethroughs. If you're striking through, typically means it no longer applies and should be removed.

[ringerc]

Updated. Better? I'd rather not remove the section completely, especially since expiry is not enabled by default.

[ringerc]

Rebased to current master and I think I should've addressed the review comments @dhawton and @zirain