Enable mining of sand when double click to mine is enabled (#4788)

* Sand mineable with double click to mine enabled

Since the only reason sand is un-mineable in the first place is because accidentally mining it is annoying, it should be enabled for double click to mine.

* only show sand as mineable when double click mine is enabled

Co-authored-by: Anuken <arnukren@gmail.com>

core/src/mindustry/input/InputHandler.java

@@ -1027,7 +1027,7 @@ public abstract class InputHandler implements InputProcessor, GestureListener{
         return !Core.scene.hasMouse()
             && tile.drop() != null
             && player.unit().validMine(tile)
-            && !(tile.floor().playerUnmineable && tile.overlay().itemDrop == null)
+            && !((!Core.settings.getBool("doubletapmine") && tile.floor().playerUnmineable) && tile.overlay().itemDrop == null)
             && player.unit().acceptsItem(tile.drop())
             && tile.block() == Blocks.air;
     }