Merge pull request #699 from klihub/fixes/e2e/apt-key-fetch-redirects

e2e: follow HTTP redirects when fetching apt repo keys.

demo/lib/distro.bash

@@ -170,7 +170,7 @@ debian-install-repo-key() {
         vm-command "apt-get update && apt-get install -y gnupg2"
     }
     for key in "$@"; do
-        vm-command "curl -s $key | apt-key add -" ||
+        vm-command "curl -L -s $key | apt-key add -" ||
             command-error "failed to install repo key $key"
     done
 }