[BUG]: fix dev k8s query-service-cache mount with subpath

[MrCroxx]

Description of changes

Summarize the changes made by this PR.

• Improvements & Bug fixes
  • Fix dev k8s volume query-service-cache mount with subPathExpr to make sure each pod owns its exclusive cache directory.

Test plan

How are these changes tested?

• Tests pass locally with pytest for python, yarn test for js, cargo test for rust

Documentation Changes

Are all docstrings for user-facing APIs updated if required? Do we need to make documentation changes in the docs section?

[github-actions]

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[jasonvigil]

Would we want this fix for the compaction cache also?

chroma/k8s/distributed-chroma/templates/compaction-service.yaml

Line 39 in ec1f94c

- name: compaction-service-cache

[HammadB]

I don't think we want this fix as is - because my_member_id for the same physical node could change after a deploy, so the cache could be incoherent for that node.

We should think of an alternative that gives similar semantics for dev (in prod nodes are 1:1 with pods so this won't happen).

[MrCroxx]

I don't think we want this fix as is - because my_member_id for the same physical node could change after a deploy, so the cache could be incoherent for that node.

Got it. I'm not sure which method Chroma Cloud uses to restrict the affinity. It would be better if there is some other env we can use to keep it coherent.

We should think of an alternative that gives similar semantics for dev (in prod nodes are 1:1 with pods so this won't happen).

Imo, if possible, I still prefer to use some form of coherent ID to address this issue. Firstly, using subpaths is compatible with the default 1:1 deployment. Secondly, this approach would prevent potential future expansions.