fix(tests): pass --no-onboard in test_issue21_acceptance and shift evidence pins (Issue #68, review round 1)

tests/test_issue68_onboard_default.py

@@ -245,4 +245,3 @@ def test_prepare_no_onboard_sends_none(ctl, mock_herdr, mock_agents):
                 assert rec.get("agent_session") != f"herdr:{row['name']}", rec
     finally:
         subprocess.run(["git", "worktree", "remove", "--force", str(wt)], cwd=str(main), capture_output=True)
-