Fix iptables commands, remove Pipfile.lock

Description

Removes the generated Pipfile.lock before scanning to simulate scanning without a lock file. The lock file is currently generated by the dependency installation that happens in the before_script. With the addition of the Pipfile.lock parser, this will cause the expectations to mismatch if not removed i.e. the expected file scanned will be Pipfile while the result will be Pipfile.lock.

Issue(s)

Relates to Enable development dependency scanning in pipen... (gitlab-org/gitlab#375505 - closed)