rhg: demonstrate that rhg breaks on non-generaldelta revlogs Differential Revision: https://phab.mercurial-scm.org/D11880

tests: add a short `sleep` in test-status.t With dirstate-v2 and rhg both enabled, this test would sometimes fail for me with: ``` --- tests/test-status.t +++ tests/test-status.t#dirstate-v2.err @@ -943,7 +943,7 @@ $ rm subdir/unknown $ hg status $ hg debugdirstate --all --no-dates | grep '^ ' - 0 -1 set subdir + 0 -1 unset subdir ``` Meaning that `status` did not write a directory mtime in the dirstate as expected. This can happen if the observed mtime of the directory is the same as "current time" at the start of `status`. This current time is obtained by creating a temporary file and checking its mtime. Even with ext4 on my system being able to store nanosecond precision, identical mtime for successive but separate operations is still possible becuse the kernel may cache the current time: https://stackoverflow.com/a/14393315/1162888 0.1 second should be enough for this cache to be updated, without significantly slowing down the test. Differential Revision: https://phab.mercurial-scm.org/D11900