tmf.ctf: Delete supplementary files after tests

tmf.ctf: Delete supplementary files after tests

This way, each test has a reproducible state: without supplementary
file, otherwise some tests were using the supplementary files from
previous runs. It found bugs in other patches, but they were not related
to this.

Change-Id: I92cabd22d2193e1cd0fe43ce1f32be0e05b9fd20
Signed-off-by: Geneviève Bastien <gbastien+lttng@versatic.net>
Reviewed-on: https://git.eclipse.org/r/84034
Reviewed-by: Hudson CI
Reviewed-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Tested-by: Matthew Khouzam <matthew.khouzam@ericsson.com>