babeltrace: Remove leftovers

babeltrace: Remove leftovers

It seems like these files should have been removed when removing the
babeltrace Python bindings in commit

    1c81bd8895c0 ("Remove babeltrace 1 Python bindings and tests")

Right now, the test causes a "make check" failure, because it tries to
import the babeltrace Python package, which no longer exists.

Change-Id: Ied4871ec23444776fca601b6f78b583ef8137c81
Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Reviewed-on: https://review.lttng.org/c/babeltrace/+/1125
Reviewed-by: Philippe Proulx <eeppeliteloop@gmail.com>