Consider excluding dracut-config-rescue in ostree-based images

[achilleas-k]

Installing dracut-config-rescue will inevitably generate a secondary rescue kernel, which will make rpm-ostree compose fail with something like:

Preparing kernel
error: Finalizing rootfs: During kernel processing: Multiple vmlinuz- in usr/lib/ostree-boot, occurrences 'usr/lib/ostree-boot/vmlinuz-5.14.0-427.13.1.el9_4.aarch64' and 'usr/lib/ostree-boot/vmlinuz-0-rescue-ffffffffffffffffffffffffffffffff'
Traceback (most recent call last):
  File "/run/osbuild/bin/org.osbuild.ostree.preptree", line 176, in <module>
    r = main(args["tree"], args["options"])
  File "/run/osbuild/bin/org.osbuild.ostree.preptree", line 169, in main
    subprocess.run(["rpm-ostree", "compose", "postprocess",
  File "/usr/lib64/python3.9/subprocess.py", line 528, in run
    raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['rpm-ostree', 'compose', 'postprocess', '/run/osbuild/tree', '/tmp/tmpx7i5hvm5.json']' returned non-zero exit status 1.

One solution would be to disable dracut in the rpm stage (which is an option that exists in osbuild's org.osbuild.rpm stage).
Alternatively, we can exclude dracut-config-rescue in ostree-based builds, but our excludes aren't considered when depsolving user packages.