There are several packages that fetch their sources over the Git
protocol. That is, 'git://'.

This protocol is unauthenticated, which is not great, although not 100%
terrible since we know the hash of what we are trying to fetch. Also, it
uses port 9418 which is blocked more often than 443 or 80.

Let's change these packages to use HTTPS or HTTP!

~/guix/gnu/packages% grep -rI 'git://'
pumpio.scm:                    (url "git://pumpa.branchable.com/")
fltk.scm:                    (url "git://git.tuxfamily.org/gitroot/non/fltk.git")
microcom.scm:                    (url "git://git.pengutronix.de/git/tools/microcom.git")
rdesktop.scm:                    (url "git://github.com/FreeRDP/FreeRDP.git")
gnunet.scm:                      (url "git://git.sv.gnu.org/guix/gnunet.git")
suckless.scm:               (url "git://git.2f30.org/human.git")
admin.scm:                      (url "git://github.com/TrilbyWhite/interrobang")
embedded.scm:                      (url "git://git.zapb.de/libjaylink.git")
embedded.scm:                      (url "git://git.code.sf.net/p/openocd/code.git")
version-control.scm:             (url "git://myrepos.branchable.com/myrepos")
audio.scm:                    (url "git://git.ardour.org/ardour/ardour.git")
emacs.scm:                    (url "git://git.hcoop.net/git/bpt/emacs.git")
messaging.scm:                    (url "git://git.psyced.org/git/psyclpc")
music.scm:                      (url "git://git.tuxfamily.org/gitroot/non/non.git")
python.scm:             (url "git://github.com/tgalal/python-axolotl-curve25519")
web.scm:                    (url "git://git.libwebsockets.org/libwebsockets")
gnome.scm:                      (url "git://git.gnome.org/byzanz")
guile.scm:                    (url "git://git.hcoop.net/git/bpt/guile.git")
guile.scm:                      (url "git://dthompson.us/guile-syntax-highlight.git")
java.scm:                      (url "git://git.savannah.gnu.org/classpath.git")
shells.scm:                    (url "git://github.com/rakitzis/rc.git")