packit: Build PRs into default packit COPRs

Building all PRs of all container projects into the same COPR does not
properly isolate PRs from each other: E.g. a podman PR currently runs
against whichever crun PR was opened/updated last; in other words,
sending a broken crun PR will instantly break tests for all subsequent
podman runs.

To avoid that, change the copr_build configuration to use the packit
default COPRs, which are specific to the particular PR, and disappear
after a few weeks. Projects should only run against what landed in
our dependencies' main branches, i.e. the podman-next COPR.

Note that this does not preclude testing a podman PR against a e.g. a
crun PR: This can be explicitly requested [1]. But most PRs don't change
the API and thus should default to isolation.

[1] https://packit.dev/posts/testing-farm-triggering

[NO NEW TESTS NEEDED]

Signed-off-by: Martin Pitt <mpitt@redhat.com>

.packit.yaml

@@ -2,27 +2,34 @@
 # See the documentation for more information:
 # https://packit.dev/docs/configuration/
 
-# Build targets can be found at:
-# https://copr.fedorainfracloud.org/coprs/rhcontainerbot/packit-builds/
-
 specfile_path: rpm/podman.spec
 upstream_tag_template: v{version}
 
-jobs:
-  - &copr
-    job: copr_build
-    trigger: pull_request
-    owner: rhcontainerbot
-    project: packit-builds
-    enable_net: true
 srpm_build_deps:
   - make
 
-  - <<: *copr
+jobs:
+  - job: copr_build
+    trigger: pull_request
+    enable_net: true
+    # keep in sync with https://copr.fedorainfracloud.org/coprs/rhcontainerbot/podman-next
+    targets:
+      - fedora-all-x86_64
+      - fedora-all-aarch64
+      - centos-stream+epel-next-8-x86_64
+      - centos-stream+epel-next-8-aarch64
+      - centos-stream+epel-next-9-x86_64
+      - centos-stream+epel-next-9-aarch64
+    additional_repos:
+      - "copr://rhcontainerbot/podman-next"
+
   # Run on commit to main branch
+  - job: copr_build
     trigger: commit
     branch: main
+    owner: rhcontainerbot
     project: podman-next
+    enable_net: true
 
   - job: propose_downstream
     trigger: release