Ignore variant when looking up command for platform in entrypoint

[imjasonh]

Changes

Fixes #4548

/kind bug

This change changes our runtime platform selection logic to allow matching platforms that don't match the CPU variant, since some indexes only provide the variant-less platform, and should be chosen in that case rather than failing.

If the platform's command is found including the CPU variant, it will be used. If not, we'll also check if there's a variant-less platform that matches, and if so, we'll use that command.

cc @vaikas

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Release Notes

Loosen runtime platform selection logic to account for platforms with CPU variants

[imjasonh]

@vaikas If you could try this out and see if it fixes your bug that'd be helpful. If not, I have another idea but it's a bit more involved than this.

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
cmd/entrypoint/main.go	0.0%	14.0%	14.0

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
cmd/entrypoint/main.go	0.0%	14.0%	14.0

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
cmd/entrypoint/main.go	0.0%	14.0%	14.0

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
cmd/entrypoint/main.go	0.0%	14.0%	14.0

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
cmd/entrypoint/main.go	0.0%	14.0%	14.0

[vaikas]

Thanks @imjasonh works fantastic with this change!!!

[dlorenc]

/approve

Thanks!

[vdemeester]

/lgtm
/meow

[tekton-robot]

@vdemeester:

In response to this:

/lgtm
/meow

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[tekton-robot]

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This pull-request has been approved by: dlorenc, vdemeester

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