Fix for v4 of the upload and download artifacts actiosn

These actions require artifact names to be unique across runs. We
achieve this by uploading unique names, then downloading all of them.

Signed-off-by: Nic Cope <nicc@rk0n.org>

Author: negz

.github/workflows/ci.yml

@@ -118,7 +118,7 @@ jobs:
       - name: Upload Single-Platform Package
         uses: actions/upload-artifact@v4
         with:
-          name: packages
+          name: package-${{ matrix.arch }}
           path: "*.xpkg"
           if-no-files-found: error
           retention-days: 1
@@ -137,8 +137,8 @@ jobs:
       - name: Download Single-Platform Packages
         uses: actions/download-artifact@v4
         with:
-          name: packages
           path: .
+          merge-multiple: true
 
       - name: Setup the Crossplane CLI
         run: "curl -sL https://raw.githubusercontent.com/crossplane/crossplane/master/install.sh | sh"