Add the '-internal' suffix to IoT images

Because the test logs are private, the visibility is '-internal', so
update the test cases to match.

https://phabricator.apertis.org/T8949



Signed-off-by: Ryan Gonzalez <ryan.gonzalez@collabora.com>

test-cases/iot-suite-connector.yaml

@@ -2,7 +2,7 @@ metadata:
   name: iot-suite-connector
   format: "Apertis Test Definition 1.0"
   image-types:
-    iot: [ amd64, arm64, armhf ]
+    iot: [ amd64-internal, arm64-internal, armhf-internal ]
   image-deployment:
     - APT
   group: "iot"