Update boot.lua

Removing the alpha variable allows anyone who overwrote the setColor function to see errorhandler's print.
e.g. I'm overwriting the setColor function to accommodate 0-255 values and the error message is being printed with 1/255 alpha (invisible).
Removing the 1 will print the message in black.

P.S. I'm currently overwriting errorhandler for this, but I assume others are also overwriting setColor and see no error messages.

src/scripts/boot.lua

@@ -673,7 +673,7 @@ function love.errhand(msg)
 	love.graphics.reset()
 	local font = love.graphics.setNewFont(14)
 
-	love.graphics.setColor(1, 1, 1, 1)
+	love.graphics.setColor(1, 1, 1)
 
 	local trace = debug.traceback()