travis: include Debian targets too

.travis.yml

@@ -1,4 +1,4 @@
 import:
   - source: QubesOS/qubes-continuous-integration:R4.1/travis-base-r4.1.yml
   - source: QubesOS/qubes-continuous-integration:R4.1/travis-dom0-r4.1.yml
-  - source: QubesOS/qubes-continuous-integration:R4.1/travis-vms-rpm-r4.1.yml
+  - source: QubesOS/qubes-continuous-integration:R4.1/travis-vms-r4.1.yml