do not run E2E test on short mode

selfupdate/e2e_test.go

@@ -5,12 +5,13 @@ import (
 	"testing"
 )
 
-func init() {
-	if err := exec.Command("go", "build", "../cmd/selfupdate-example/main.go").Run(); err != nil {
-		panic(err)
-	}
-}
-
 func TestRunSelfUpdateExample(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping test in short mode.")
+	}
+
+	if err := exec.Command("go", "build", "../cmd/selfupdate-example").Run(); err != nil {
+		t.Fatal(err)
+	}
 	t.Fatal("TODO")
 }