github: run tests inside a fedora container

Running the tests inside fedora means we get much more meaningful
results as we will have all the required packaes and there will
be no need to skip tests.

.github/workflows/go.yaml

@@ -14,13 +14,17 @@ on:  # yamllint disable-line rule:truthy
 jobs:
   build:
     runs-on: ubuntu-latest
+    container: registry.fedoraproject.org/fedora:41
+    env:
+      # workaround for expired cert at source of indirect dependency
+      # (go.opencensus.io/trace)
+      GOPROXY: "https://proxy.golang.org,direct"
     steps:
       - uses: actions/checkout@v4
-      - uses: ./.github/actions/testdeps
-      - name: Set up Go
-        uses: actions/setup-go@v5
-        with:
-          go-version: 'stable'
+      - name: Install dependencies
+        run: |
+          # we have the same build-deps as the images library
+          curl -sL https://raw.githubusercontent.com/osbuild/images/refs/heads/main/test/scripts/install-dependencies | bash
       - name: Build
         run: go build -v ./...
       - name: Test