Sort supported architectures

Most of test cases sort supported architectures by relevance instead of
alphabetically, so apply the same principle in general to keep consistency.

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

test-cases/apertis-update-manager-rollback.yaml

@@ -2,7 +2,7 @@ metadata:
   name: apertis-update-manager-rollback
   format: "Apertis Test Definition 1.0"
   image-types:
-    fixedfunction: [ amd64, armhf, arm64 ]
+    fixedfunction: [ armhf, arm64, amd64 ]
   image-deployment:
     - OSTree
   type: functional