remove minetest_directory before clone it

minetest-server.sh

@@ -90,6 +90,7 @@ copyConfMinetestServer (){
 copyDefaultWorld (){
     taskName="Download minetest_game"; echo -e "\n[+][$taskName]"
     cd $minetestDirResources/worlds
+    rm -rf $minetestDirResources/worlds/minetest_game
     git clone https://github.com/minetest/minetest_game.git minetest_game
     isOK
 }