e2e: load to docker store

[crazy-max]

Signed-off-by: CrazyMax crazy-max@users.noreply.github.com

[crazy-max]

https://github.com/docker/buildx/actions/runs/3670274233/jobs/6204713067#step:11:205

#12 exporting to docker image format
#12 ERROR: docker exporter does not currently support exporting manifest lists
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 > exporting to docker image format:
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ERROR: failed to solve: docker exporter does not currently support exporting manifest lists

@jedevc I think we need changes here to properly handle multi-platform for OCI exporter like we do for the image one.

[jedevc]

@crazy-max I think this should be solved by moby/buildkit#3380.

It's a result of buildx attempting to attach provenance attestations by default, but, we need to filter out the inline attestations for the docker exporter just like we do for the local and tar exporter.

[crazy-max]

@jedevc Nice, didn't catch that PR.