tests/functional: Provide the user with hints where to find more log files

tests/functional: Provide the user with hints where to find more log files

Since the base.log and console.log files are not referenced from the
meson test logs yet, they might be hard to find for the casual users.
Thus let's print some hints in case a test case failed. For this we
have to run unittest.main() with exit=False to get the results of the
testing. Then we can iterate through the failed test cases to print
out the information accordingly.

Message-ID: <20241105123849.359391-1-thuth@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>