trivial: Don't run emulation tests without CI_NETWORK set

autopkgtest in Ubuntu has a proxy configuration issue on some autopkgtest
hosts that is causing it to sometimes fail.

This needs to get fixed on the server end but it's actually surprising
it was being run in the first place because we snuck tests in with
new artifacts that depended on LVFS now.

We should gate this running behind CI_NETWORK, just like we do for
other test data.

Link: https://bugs.launchpad.net/ubuntu/+source/fwupd/+bug/2021908
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>

data/installed-tests/fwupd.sh

@@ -12,7 +12,7 @@ run_test()
 
 run_device_tests()
 {
-	if [ -d @devicetestdir@ ]; then
+	if [ -n "$CI_NETWORK" ] && [ -d @devicetestdir@ ]; then
 		# grab device tests from the CDN to avoid incrementing the download counter
 		export FWUPD_DEVICE_TESTS_BASE_URI=http://cdn.fwupd.org/downloads
 		for f in `grep --files-with-matches -r emulation-url @devicetestdir@`; do