add worktree test

.gitignore

@@ -1,3 +1,5 @@
+.test_info.*
+lastlog.jsonl
 *.bak
 lab
 .envrc

xt/worktree-clean.t

@@ -0,0 +1,12 @@
+use Test2::V0;
+
+use Git::Wrapper;
+
+my $git = Git::Wrapper->new('.');
+
+my $status = $git->status;
+
+# note: 'yath' might create .test_info and lastlog.jsonl files
+ok !$status->is_dirty => "worktree is clean";
+
+done_testing;