tests: skip properly with git <2.6

Tested with git 1.8.3.1 on CentOS 7.x

`plan skip_all => ...' doesn't work after some tests have run,
we have to call skip() instead.

1 files changed, 1 insertions, 1 deletions

diff --git a/t/nntpd.t b/t/nntpd.t
index 6c100138..18aaccbe 100644
--- a/t/nntpd.t
+++ b/t/nntpd.t
@@ -13,11 +13,11 @@ use Net::NNTP;
 use Sys::Hostname;
 use POSIX qw(_exit);
 use Digest::SHA;
-use_ok 'PublicInbox::Msgmap';
 
 # t/nntpd-v2.t wraps this for v2
 my $version = $ENV{PI_TEST_VERSION} || 1;
 require_git('2.6') if $version == 2;
+use_ok 'PublicInbox::Msgmap';
 my $lsof = which('lsof');
 my $fast_idle = eval { require Linux::Inotify2; 1 } //
                 eval { require IO::KQueue; 1 };