Replace KeyValuePairs' internal BTreeSet with BTreeMap

[nightkr]

Description

Fixes #887

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1. Changes are OpenShift compatible
2. CRD changes approved
3. Integration tests passed (for non trivial changes)

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1. Code contains useful comments
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3. Documentation added or updated
4. Changelog updated
5. Cargo.toml only contains references to git tags (not specific commits or branches)

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[Techassi]

Approved in general, but maybe we should close this one in favour of #889?

[nightkr]

Depends. #889 breaks a lot of the API, so I'd prioritize getting the smaller fix in to avoid delaying the rest of the release.

[Techassi]

Alright, makes sense. Let's delay #889 until the 24.11 release is done.