[1.10.2] Small boilers include bottom side when outputting steam

[MauveCloud]

In 5.09 and earlier, small boilers would output steam to all sides except the bottom (edit: or the front, looking at the code), making it safe to use the bottom for pipes to input water into the boiler (without needing pump covers or shutter modules to prevent backflow). However, with 5.10.40, I've determined that a small boiler will output steam to the bottom as well - with small copper pipes that have not been connected to the top or sides, and a boiler that has cooled down, when I attach a wooden pipe next to the pipe directly under the boiler, it ignites immediately. I also have a steam macerator nearby, but I can tell this is not from the machines, because if I put planks in the same place, they do not ignite.