ci: Build latest skopeo for ubuntu

So that we can drop support for the hacky "copy to temporary OCI"
code.

Signed-off-by: Colin Walters <walters@verbum.org>

.github/workflows/ci.yml

@@ -116,22 +116,45 @@ jobs:
         run: sudo tar -C / -xvf bootc.tar.zst
       - name: Integration tests
         run: bootc internal-tests run-container-integration
+  build-skopeo-ubuntu:
+    name: "Build skopeo git main for ubuntu"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          repository: containers/skopeo
+          path: skopeo
+      - name: Install build deps
+        run: |
+          sudo sed -ie s,'# deb-src,deb-src,' /etc/apt/sources.list
+          sudo apt update
+          sudo apt build-dep -y skopeo
+      - uses: actions/setup-go@v4
+        with:
+          go-version: '>=1.20'
+      - name: Build skopeo
+        run: cd skopeo && make bin/skopeo PREFIX=/usr
+      - name: Upload binary
+        uses: actions/upload-artifact@v4
+        with:
+          name: skopeo-ubuntu
+          path: skopeo/bin/skopeo
   privtest-alongside:
     name: "Test install-alongside"
-    needs: build-fedora
+    needs: [build-fedora, build-skopeo-ubuntu]
     runs-on: ubuntu-latest
     steps:
+      - name: Download
+        uses: actions/download-artifact@v4
+        with:
+          name: skopeo-ubuntu
+      - run: chmod a+x skopeo && sudo mv skopeo /usr/bin
       - name: Download
         uses: actions/download-artifact@v3
         with:
           name: bootc.tar.zst
       - name: Install
         run: tar -xvf bootc.tar.zst
-      - name: Update host skopeo
-        run: |
-          echo 'deb http://cz.archive.ubuntu.com/ubuntu lunar main universe' | sudo tee -a /etc/apt/sources.list
-          sudo apt update
-          sudo apt upgrade skopeo
       - name: Integration tests
         run: |
           set -xeuo pipefail