add test env for debian 10

Signed-off-by: Cenk Kuecuek <git@cenk.me>

Author: cnkk

.travis.yml

@@ -38,6 +38,11 @@ env:
 #    init: /lib/systemd/systemd
 #    run_opts: "--privileged --volume=/sys/fs/cgroup:/sys/fs/cgroup:ro"
 
+  - distro: debian10
+    version: latest
+    init: /lib/systemd/systemd
+    run_opts: "--privileged --volume=/sys/fs/cgroup:/sys/fs/cgroup:ro"
+
   - distro: amazon
     init: /lib/systemd/systemd
     version: latest