The v2 CI pipeline contains most of the functionality of the old pipeline. To clean the overview in buildkite up, we should:

• remove scionproto pipeline (and associated files);
• remove acceptance pipeline (and associated files);
• rename scionproto2 pipeline to scion pipeline; change description to "Full test suite (unit, integration, acceptance, end to end)";
• remove scionproto nightly pipeline;
• add scion nightly pipeline; have it be the same as the new scion pipeline for now;