Automatically set GOMEMLIMIT based on cgroups memory limits

[naemono]

Resolves #8790

This adds automemlimit to the ECK operator to automatically set GOMEMLIMIT to 90% of the CGroup's memory limit. This essentially makes golang's garbage collector more aggressive once memory usage has hit 90% of the defined memory limit for the container.

More information about GOMEMLIMIT here.

TODO

• Verification via exported metrics of setting. (go_gc_gomemlimit_bytes: 966367641, mem_limit: 1073741824)
• Investigating whether documentation would be appropriate.

[Copilot]

Pull Request Overview

This PR adds the automemlimit library to automatically set GOMEMLIMIT to 90% of the container's cgroup memory limit, making Go's garbage collector more aggressive as memory usage approaches the defined container limit.

• Adds automemlimit dependency to automatically manage Go's memory limit
• Imports the library with a blank import to activate its side effects
• Includes documentation comment explaining the 90% memory limit behavior

Reviewed Changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated no comments.

File	Description
go.mod	Adds automemlimit and memory dependencies as indirect imports
cmd/main.go	Imports automemlimit library with blank import and explanatory comment

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[prodsecmachine]

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[github-actions]

🔍 Preview links for changed docs

• docs/reference/third-party-dependencies/main.md