runtests.pl: kill processes locking test log files #6179
That is correct, but it would still be good to know if the files are kept open while they should already be closed. So the detection part is probably a good idea, but maybe not the process killing part.
While Msys2 has a pwd binary which supports -L, Msys1 only has a shell built-in with that feature. Reviewed-by: Jay Satiro Part of #6179