Fix #130903: Overlay-Next: Crash using asan in Relation drawing

The cast `float4(float3&)` is invalid and was casted to
`float4(float *)` which read past the end of the vector.

source/blender/draw/engines/overlay/overlay_next_private.hh

@@ -766,7 +766,7 @@ struct VertexPrimitiveBuf {
 
   void append(const float3 &position, const float4 &color)
   {
-    data_buf.append({float4(position), color});
+    data_buf.append({float4(position, 0.0f), color});
   }
 
   void end_sync(PassSimple::Sub &pass, GPUPrimType primitive)