bitbake: tests/fetch: Add ftp test url

Add in a tets ftp url so we ensure ftp urls contnue to work after the loss
of the ftp.gnu.org ones.

(Bitbake rev: e1e8565b5e19dd3f7ef6e7e41932456adaa3df81)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/tests/fetch.py

@@ -837,6 +837,7 @@ class FetchCheckStatusTest(FetcherTest):
                       "https://yoctoproject.org/documentation",
                       "http://downloads.yoctoproject.org/releases/opkg/opkg-0.1.7.tar.gz",
                       "http://downloads.yoctoproject.org/releases/opkg/opkg-0.3.0.tar.gz",
+                      "ftp://sourceware.org/pub/libffi/libffi-1.20.tar.gz",
                       "http://ftp.gnu.org/gnu/autoconf/autoconf-2.60.tar.gz",
                       "https://ftp.gnu.org/gnu/chess/gnuchess-5.08.tar.gz",
                       "https://ftp.gnu.org/gnu/gmp/gmp-4.0.tar.gz",