packit: Re-disable Fedora 42

The cloud images are missing [1] and not even COPR works.

Also move the aarch64 test from -latest (which is 42 now, which
doesn't work) to -latest-stable (which is 41).

[1] https://pagure.io/fedora-infrastructure/issue/12389

packit.yaml

@@ -20,8 +20,9 @@ jobs:
     trigger: pull_request
     targets:
       - fedora-41
-      - fedora-42
-      - fedora-latest-aarch64
+      # https://pagure.io/fedora-infrastructure/issue/12389
+      # - fedora-42
+      - fedora-latest-stable-aarch64
       - fedora-development
       - centos-stream-9-x86_64
       - centos-stream-9-aarch64