selftests/bpf: remove duplicated word from test offloads

Trivial removal of duplicated "mode" in error message.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/testing/selftests/bpf/test_offload.py

@@ -830,7 +830,7 @@ try:
     check_extack_nsim(err, "program loaded with different flags.", args)
     ret, _, err = sim.unset_xdp("", force=True,
                                 fail=False, include_stderr=True)
-    fail(ret == 0, "Removed program with a bad mode mode")
+    fail(ret == 0, "Removed program with a bad mode")
     check_extack_nsim(err, "program loaded with different flags.", args)
 
     start_test("Test MTU restrictions...")