Remove redundant line in copyright header

Really should have noticed this when committing it.

src/main/java/dan200/computercraft/api/lua/LuaException.java

@@ -2,7 +2,6 @@
  * This file is part of the public ComputerCraft API - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
  * For help using the API, and posting your mods, visit the forums at computercraft.info.
- *
  */
 
 package dan200.computercraft.api.lua;