chore: remove test containerfile

### What does this PR do?

Removes an old bootc container file that is no longer needed / should
not be referenced (uses an old FROM, as well as very insecure RUN
command)

### Screenshot / video of UI

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screenshots or screencasts showing the difference -->

N/A

### What issues does this PR fix or reference?

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repository (or from another issue tracker). -->

N/A

### How to test this PR?

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do not forget to provide unit/component tests -->

N/A

Signed-off-by: Charlie Drage <charlie@charliedrage.com>