old signals that are no longer in the dbc still show up as signals you can view

[annamur14]

• seen on my macbook air m2 but its probably an issue on all platforms
• in the "all" tab, in the signals column on the left, can we just display signals that exist in the DBC that's been most recently uploaded
• under the "all" tab in the signal column, old signals (like BMS Cell_OCV_Offset_X) still show up, even though they're not present in the most recent CAN DBC