Always use named arguments when calling run_subprocess_x

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Utils: Add input (file) argument to run_subprocess_x functions

Signed-off-by: Tomas Hozza <thozza@redhat.com>
PatchHelper: remove unused argument of patch_command()

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Refactor code calling run_subprocess_x

Don't use shell=True if completely necessary. It is more safe
not to use it. Also pass cmd as list of strings.

Signed-off-by: Tomas Hozza <thozza@redhat.com>
PatchHelper: cosmetic changes to list comprehension and log msgs

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Tests: Update and extend ProcessHelper tests

Signed-off-by: Tomas Hozza <thozza@redhat.com>