Change ade test priority to medium

Since the functionality provided by ade has little value after the switch
to Flatpak, change the test priority to medium.

Signed-off-by: Walter Lozano <walter.lozano@collabora.com>

test-cases/ade-commands.yaml

@@ -9,7 +9,7 @@ metadata:
   group: "sdk"
   type: functional
   exec-type: automated
-  priority: critical
+  priority: medium
   maintainer: "Apertis Project"
   description: "Test ade command and sub-command with default and custom options
                 and arguments."