Bug 1503817: add missing checkout directory argument to `configure_git` call r=glob

In bug 1481425 I added an argument to `configure_git` for
the root directory of the current Firefox checkout, so
we could check for and remove the MozReview commit message
hook. I overlooked one other call to that function in
`bootstrap.py`, which is now failing due to too few
arguments. This commit adds the missing parameter.

Differential Revision: https://phabricator.services.mozilla.com/D10556

--HG--
extra : moz-landing-system : lando

python/mozboot/mozboot/bootstrap.py

@@ -468,7 +468,8 @@ class Bootstrapper(object):
                 should_configure_git = self.hg_configure
 
             if should_configure_git:
-                configure_git(self.instance.which('git'), state_dir)
+                configure_git(self.instance.which('git'), state_dir,
+                              checkout_root)
 
         # Offer to clone if we're not inside a clone.
         have_clone = False