test(e2e): remove legacy scaffolding after Ginkgo migration

[IrvingMg]

Description

This PR cleans up the remaining unused code from the migration.

Related issues

• Part of Migrate E2E tests to Ginkgo framework #381

How was this tested?

• make e2etest

LLM usage

Claude Code (Opus 4.6)

Checklist

• I have read the contribution guide.
• The linter passes locally (make lint).
• The e2e tests of at least one tool pass locally (make test_ctr, make test_nerdctl, make test_docker, make test_crictl).
• If LLMs were used: I have read the llm policy.

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[cmainas]

Hello @IrvingMg thank you for the cleanup. One comment that we can discuss over.

I think it would be better to place all the new functions of tests/e2e/common.go (e.g. getTestImages) in a separate file and keep the common go file as a file that contains common functions for the various tools. Maybe, a better file to place them would be tests/e2e/utils.go or rename tests/e2e/setup_test.go.

[IrvingMg]

Hello @IrvingMg thank you for the cleanup. One comment that we can discuss over.

I think it would be better to place all the new functions of tests/e2e/common.go (e.g. getTestImages) in a separate file and keep the common go file as a file that contains common functions for the various tools. Maybe, a better file to place them would be tests/e2e/utils.go or rename tests/e2e/setup_test.go.

Done. Moved the image management functions and constants to utils.go.