Make sure via-gap-same-as-trace-gap gets turned off for board settings.

Fixes https://gitlab.com/kicad/code/kicad/issues/12236

pcbnew/router/pns_kicad_iface.cpp

@@ -651,6 +651,7 @@ bool PNS_KICAD_IFACE_BASE::ImportSizes( PNS::SIZES_SETTINGS& aSizes, PNS::ITEM*
     aSizes.SetDiffPairWidth( diffPairWidth );
     aSizes.SetDiffPairGap( diffPairGap );
     aSizes.SetDiffPairViaGap( diffPairViaGap );
+    aSizes.SetDiffPairViaGapSameAsTraceGap( false );
 
     int      holeToHoleMin = bds.m_HoleToHoleMin;
     PNS::VIA dummyVia;