fix: Fix upgrade path 3.3.x -> 4.0.x

[sbernauer]

Description

Fixes #538

This PR also adds an upgrade test to make sure the functionality will be kept going forward.

Co-developed with @xeniape

Definition of Done Checklist

• Not all of these items are applicable to all PRs, the author should update this template to only leave the boxes in that are relevant
• Please make sure all these things are done and tick the boxes

Author

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1. Changes are OpenShift compatible
2. CRD changes approved
3. CRD documentation for all fields, following the style guide.
4. Helm chart can be installed and deployed operator works
5. Integration tests passed (for non trivial changes)
6. Changes need to be "offline" compatible

Reviewer

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1. Code contains useful comments
2. Code contains useful logging statements
3. (Integration-)Test cases added
4. Documentation added or updated. Follows the style guide.
5. Changelog updated
6. Cargo.toml only contains references to git tags (not specific commits or branches)

Acceptance

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1. Feature Tracker has been updated
2. Proper release label has been added
3. Roadmap has been updated

[NickLarsenNZ]

LGTM

[NickLarsenNZ]

Btw, you can add a Co-authered-by trailer to the commit to give @xeniape attribution (not sure if Co-developed has any significance in github if that's what you were going for).

[sbernauer]

Started https://testing.stackable.tech/view/02%20Operator%20Tests%20(custom)/job/hive-operator-it-custom/6

[NickLarsenNZ]

LGTM

[sbernauer]

https://testing.stackable.tech/view/02%20Operator%20Tests%20(custom)/job/hive-operator-it-custom/7/

[NickLarsenNZ]

LGTM, thanks for the upgrade test

[sbernauer]

All tests passed