tests: move bfd over gre to extended tests

This test should be fixed or removed.
EXTENDED_TESTS should not become "BROKEN_TESTS"

Type: test

Change-Id: Id998f0d3b7bd31100f917d076fbd7ddb46d99ed2
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>
diff --git a/test/test_bfd.py b/test/test_bfd.py
index 36356c7..7d87a92 100644
--- a/test/test_bfd.py
+++ b/test/test_bfd.py
@@ -1790,6 +1790,7 @@
                              packet[IPv6].dst)
 
 
+@unittest.skipUnless(running_extended_tests, "part of extended tests")
 class BFDTunTestCase(VppTestCase):
     """ BFD over GRE tunnel """