[kdump] don't report failure for tests that depend on vmcore created by previous test [moved to RHELTEST-152]

This issue has been closed and moved to JIRA: https://issues.redhat.com/browse/RHELTEST-152

Please continue with your actions and comments in the linked Jira ticket.

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For example:

kdump/analyse-dmesg
kdump/analyse-crash-cmd

these tests require a vmcore file that is created by tests like kdump/crash-sysrq-c

if kdump/crash-sysrq-c fails to create a vmcore the kdump/crash-sysrq-c will report a failure.

I think the tests that expect the vmcore to exist shouldn't report failure in this case. I'd say the tests should just report skip.