Update test list1

Update test list1

- Avoid double slashes at beginning of filename paths.
  Leave "/" in CACHED_DIR (only sed ^$BASEDIR), then it is not
  necessary to add "/" in function do_list_tests() several times
  again and "$1" can be used instead of "/$1" there.
- This allows passing of test list1 under MSYS2 (Windows), where paths
  starting (unnecessarily) with // are not working. Exit test list1
  under Windows (MSYS2) before "Starting rrdcached..."