feat(build): Run go vet as a step in the GitHub Actions workflow

.github/workflows/build-and-test.yaml

@@ -19,6 +19,8 @@ jobs:
         run: nix-env -f '<nixpkgs>' -iA go
       - name: Check formatting
         run: "test -z $(gofmt -l .)"
+      - name: Run `go vet`
+        run: "go vet ./..."
       - name: Build Nixery
         run: "nix-build --no-out-link"
       - name: Run integration test

popcount/popcount.go

@@ -90,7 +90,7 @@ func channelMetadata(channel string) meta {
 	commit, err := ioutil.ReadAll(commitResp.Body)
 	failOn(err, "failed to read commit from response")
 	if commitResp.StatusCode != 200 {
-		log.Fatalf("non-success status code when fetching commit: %s", string(commit), commitResp.StatusCode)
+		log.Fatalf("non-success status code when fetching commit: %s (%v)", string(commit), commitResp.StatusCode)
 	}
 
 	return meta{