feat(ubi): Add and use UBI10 base image

[Techassi]

This issue tracks the addition and usage/replacement of the UBI10 base image. There are currently two options:

• Add and use the UBI10 image alongside the current UBI9 image
• Add and use the UBI10 image to completely replace the current UBI9 image

There already is a branch which includes a few basic changes to add and build the UBI10 image. This PoC worked and an image could be built, but the image was not tested to be used as the base of our operator container images.

[Techassi]

I'm happy to work on this after I've completed the work for stackabletech/stackable-cockpit#220.

[NickLarsenNZ]

@lfrancke do we need to keep the UBI9 image around (I recall needing to keep the UBI8 image maintained for some time before we dropped it)?

[lfrancke]

Help me with that question: I personally don't need it. But should we need to release a patch for e.g. 25.11 would we need the old base image around?
And if so: We don't want to ship an image based on a UBI9 that hasn't been updated for a year.

That was my only "fear" here. If that is irrational or I'm missing something then it can go. That is the only thing I want to make sure of: Being able to easily release patches for our supported SDP versions if needed.

[NickLarsenNZ]

But should we need to release a patch for e.g. 25.11 would we need the old base image around?

I think we have enough safe-guards should that happen:

• We have the release images in Harbor
  • Edit: We have nightly images, but not a tagged image for the ubi9-rust-builder: https://oci.stackable.tech/harbor/projects/12/repositories/ubi9-rust-builder/artifacts-tab
• We have git and can revert the commit that removes it just to rebuild it if we need
• We could just use ubi10 (provided we don't run into any major issues building the nightly images).

So I'd be fine with dropping it when we can show that we can build images on ubi10. Also happy to just keep it around for a release if that eases concern.

[lfrancke]

I'm happy to defer that decision to you. That was my only concern.