.cirrus.yml: Fix the env_debu_script for Windows.
.cirrus.yml: Fix the env_debu_script for Windows.

Windows's cmd.exe does not use semicolons to separate commands, plus the output
captured by Cirrus CI already contains the working directory. So just remove the
"cd" command (which prints out the working directory when given no argument).

elves/elvish,elves/elvish,elves/elvish,elves/elvish,elves/elvish