patch 8.2.4089: terminal test for current directory fails on FreeBSD

Problem:    Terminal test for current directory fails on FreeBSD.
Solution:   Skip the test.
diff --git a/src/testdir/test_terminal3.vim b/src/testdir/test_terminal3.vim
index 5e7a89f..9b5a02f 100644
--- a/src/testdir/test_terminal3.vim
+++ b/src/testdir/test_terminal3.vim
@@ -779,6 +779,8 @@
 func Test_terminal_sync_shell_dir()
   CheckUnix
   " The test always use sh (see src/testdir/unix.vim).
+  " BSD's sh doesn't seem to play well with the OSC 7 escape sequence.
+  CheckNotBSD
 
   set asd
   " , is