Fixed gettext version regex

...with the theoretical assumption that gettext may once reach a
two-digit number. Thanks Walter Doekes for noticing this potential
issue.

django/core/management/commands/makemessages.py

@@ -324,7 +324,7 @@ class Command(BaseCommand):
     @cached_property
     def gettext_version(self):
         out, err, status = gettext_popen_wrapper(['xgettext', '--version'])
-        m = re.search(r'(\d)\.(\d+)\.?(\d+)?', out)
+        m = re.search(r'(\d+)\.(\d+)\.?(\d+)?', out)
         if m:
             return tuple(int(d) for d in m.groups() if d is not None)
         else: