Detect IONOS managed Stackable clusters and skip installing releases

[sbernauer]

Without this patch demos can't be installed on IONOS managed Stackable clusters. Now it's a best-effort job as the demo might work with the operator versions of the managed stackable. Maybe we should discuss the Platform release strategy in combination with managed stackable

Review Checklist

• [ ] Code contains useful comments
• [ ] (Integration-)Test cases added (or not applicable)
• [ ] Documentation added (or not applicable)
• [ ] Changelog updated (or not applicable)
• [ ] Cargo.toml only contains references to git tags (not specific commits or branches)

Once the review is done, comment bors r+ (or bors merge) to merge. Further information

[sbernauer]

For the record: Had a quick chat with the IONOS folks. They switched to installing SDP Plattform releases. They will mark us with a label on a Namespace which SDP platform version is installed so we can pick it up and validate if the stack/demo is going to run.

[lfrancke]

Okay, let me know when that has happened and I can put it on the board.