Clean the zip in case a run has not exited properly

[jorbaum]

What is this change about?

Previously this raised "file already exists: assets/dora.zip" error

Please provide contextual information.

I am running this test suite locally with cats.sh script of kind-deployment, which basically wraps bin/test of this repository. It happens to me from time to time that CATS tests did not exit properly and a file called dora.zip prohibited my tests from rerunning due to "file already exists: assets/dora.zip" error.

Verified end-to-end against a live cf-on-kind cluster: run the real suite, SIGKILL it once assets/dora.zip appears (simulating an interrupted run so AfterSuite never cleans up), then re-run.

Before the fix — the leaked zip breaks the next run:

$ # run 1: start suite, kill it once assets/dora.zip is created (leaks the zip)
$ ls assets/dora.zip
assets/dora.zip

$ # run 2: re-run with the leaked zip present
$ CONFIG=cats-config.json go run github.com/onsi/ginkgo/v2/ginkgo .
...
file already exists: assets/dora.zip
Test Suite Failed

After the fix — same leaked zip, the re-run cleans it up and proceeds:

$ ls assets/dora.zip          # leaked from the previous killed run
assets/dora.zip

$ CONFIG=cats-config.json go run github.com/onsi/ginkgo/v2/ginkgo .
Running Suite: CATS
Will run 2 of 286 specs        # past the archive step — no "file already exists"
...

No behavior change on a normal run; this only affects re-runs after an interrupted one.

What version of cf-deployment have you run this cf-acceptance-test change against?

Newest head of develop branch.

Please check all that apply for this PR:

• introduces a new test --- Are you sure everyone should be running this test?
• changes an existing test
• requires an update to a CATs integration-config

Did you update the README as appropriate for this change?

• YES
• N/A

How many more (or fewer) seconds of runtime will this change introduce to CATs?

Less than a second.

What is the level of urgency for publishing this change?

• Urgent - unblocks current or future work
• Slightly Less than Urgent

Tag your pair, your PM, and/or team!

@beyhan @cloudfoundry/wg-app-runtime-platform

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[Dariquest]

LGTM