chore: remove flakey unit test

[AustinAbro321]

Description

The test in progress_test.go has flaked several times as of late, see https://github.com/zarf-dev/zarf/actions/runs/16759926068/job/47452261385. Time based tests look to not be consistent, they likely could be if we extended the time the test took, but that still could be subject to the same issue, or make the test take too long. Another option could be to dependency injection on the timer to allow a mock, but I feel it is not worth it in this case given the simple behavior under test.

Checklist before merging

• Test, docs, adr added or updated as needed
• Contributor Guide Steps followed

[netlify]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
see 1 file with indirect coverage changes

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[mkcp]

Understandable - shared systems like ci can halt or slowdown arbitrarily which makes timing problems worse. lgtm