libgit2: refactor tests to use managed and unmanaged transport cleanly

Refactors libgit2 checkout tests to test managed and unmanaged
transport by making sure the tests requiring unmanaged transport are run
before, any tests that require managed transport (since disabling
managed transport isn't possible). This is done via arranging the tests
carefully in alphabetically sorted names, i.e. the tests with unmanaged
transport go in `checkout_test.go`, which forces golang to run the tests
in that file before any other tests.

Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>

controllers/suite_test.go

@@ -37,6 +37,7 @@ import (
 	ctrl "sigs.k8s.io/controller-runtime"
 
 	"github.com/fluxcd/pkg/runtime/controller"
+	feathelper "github.com/fluxcd/pkg/runtime/features"
 	"github.com/fluxcd/pkg/runtime/testenv"
 	"github.com/fluxcd/pkg/testserver"
 	"github.com/go-logr/logr"
@@ -206,6 +207,8 @@ func TestMain(m *testing.M) {
 		panic(fmt.Sprintf("Failed to create a test registry server: %v", err))
 	}
 
+	fg := feathelper.FeatureGates{}
+	fg.SupportedFeatures(features.FeatureGates())
 	managed.InitManagedTransport(logr.Discard())
 
 	if err := (&GitRepositoryReconciler{