tests: use `testrepohg` in one more place in test-check-code.t
This is already used elsewhere in the test to access the current hg repo, and
avoids an error about the unknown `revlog-compression-zstd` when C extensions
aren't built. The only other such error is in test-check-interfaces.py, but I
don't see a way to avoid it other than to create an empty scratch repo.
Differential Revision: https://phab.mercurial-scm.org/D9364
$ hg init
$ touch unknown
$ touch a
$ hg add a
$ hg ci -m "1"
$ touch b
$ hg add b
$ hg ci -m "2"
Should show unknown
$ hg status
? unknown
$ hg revert -r 0 --all
removing b
Should show unknown and b removed
$ hg status
R b
? unknown
Should show a and unknown
$ ls -A
.hg
a
unknown