import: unset GIT_CONFIG with `git config --global'

GIT_CONFIG is set by -convert, and user may have it set
for other reasons.  In either case, it conflicts with
any any attempt to use `git config --global` so we have
to unset it.

This fixes t/multi-mid.t under TEST_RUN_MODE=0

diff --git a/lib/PublicInbox/Import.pm b/lib/PublicInbox/Import.pm
index 47a529ff6767fee583af0138a907a0b4ca8343d5..0aff0e9dc96e8a21e78c3f99ab34bbc089ef7303 100644 (file)
--- a/lib/PublicInbox/Import.pm
+++ b/lib/PublicInbox/Import.pm
@@ -21,6 +21,7 @@ use POSIX qw(strftime);
 
 sub default_branch () {
        state $default_branch = do {
+               delete local $ENV{GIT_CONFIG};
                my $r = popen_rd([qw(git config --global init.defaultBranch)]);
                chomp(my $h = <$r> // '');
                $h eq '' ? 'refs/heads/master' : $h;