pandar_packets sometimes contains more than one scan's worth of packets in extreme CPU load scenarios

[mojomex]

This issue occurs in at least 2ea66b6, which has been used in this analysis: TIER IV INTERNAL LINK.

This could mean that scan cutting (see #173) is not robust towards packet loss and/or reordering. For now, this is not an issue that has been observed in non-stress test scenarios and is thus not a high priority.