tests: stabilize test-persistent-nodemap.t on Windows Several issues here: - Hooks can't invoke shell scripts on Windows, so use `sh` to launch - `dd` in MSYS only recognizes `status=noxfer` - The `PATH` updating triggered a massive slowdown, but is no longer needed I have no idea why, but removing the `PATH` update substantially increased the speed of the test. It was running finishing at ~4:30 with `--debug` and ~14:50 without it, but now completes in ~2:20 on my Windows laptop. Differential Revision: https://phab.mercurial-scm.org/D10636

#require symlink

https://bz.mercurial-scm.org/1438

  $ hg init

  $ ln -s foo link
  $ hg add link
  $ hg ci -mbad link
  $ hg rm link
  $ hg ci -mok
  $ hg diff -g -r 0:1 > bad.patch

  $ hg up 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg import --no-commit bad.patch
  applying bad.patch

  $ hg status
  R link
  ? bad.patch