Use the local kubelet's cluster domain, rather than a random one

[nightkr]

Description

Part of stackabletech/issues#662, followup to #1068.

This is a breaking change (towards operators); they must now (in addition to the requirements from #1068) also provide the following environment variable:

env:
  - name: KUBERNETES_NODE_NAME
    valueFrom:
      fieldRef:
        fieldPath: spec.nodeName

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

Reviewer

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

Acceptance

• Feature Tracker has been updated
• Proper release label has been added

[nightkr]

Adapted list-op as an example: stackabletech/listener-operator#317

[sbernauer]

Will review later when I get time, just FYI that #1066 also touches CLI arguments.
Maybe you can benefit from that or the other way around

[nightkr]

Doesn't look like that touches the node name, but it probably makes sense to run the templating rollouts together.

[sbernauer]

Was thinking the same. Regarding templating I already have stackabletech/operator-templating#534

[sbernauer]

LGTM, however the tests currently fail

[sbernauer]

Also giving @razvan the chance to review

[nightkr]

Oh. Right. I had updated the code tets, but not the doctests.

[razvan]

very nice!