feat: Add support for --cap-drop

[ddl-ebrown]

• Support for --cap-add was added as part of https://github.com/GoogleContainerTools/container-structure-test/pull/327

• This rounds out the feature set to also include support for --cap-drop

• Updates tests to drop "chown" capability and verify doing so works

• closes https://github.com/GoogleContainerTools/container-structure-test/issues/389

FYI - make test fails against the head of the main branch on my M1 -- which I didn't have time to diagnose. I'm using CI to verify that the tests behave properly.

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[loosebazooka]

uh, sorry no one looked at this, I get to spend a little time now and then trying to maintain this, if you can rebase this and update it, I can merge it in.

[ddl-ebrown]

@loosebazooka updated

[ddl-ebrown]

Looks like we've got failing tests

FAIL: Run options (capabilities, bindMounts) test case failed

Will take a closer look