chore(tests): enhance and document updater NSIS test (#6556)

core/tests/app-updater/src/main.rs

@@ -7,9 +7,18 @@
 fn main() {
   let mut context = tauri::generate_context!();
   if std::env::var("TARGET").unwrap_or_default() == "nsis" {
+    // /D sets the default installation directory ($INSTDIR),
+    // overriding InstallDir and InstallDirRegKey.
+    // It must be the last parameter used in the command line and must not contain any quotes, even if the path contains spaces.
+    // Only absolute paths are supported.
+    // NOTE: we only need this because this is an integration test and we don't want to install the app in the programs folder
     context.config_mut().tauri.updater.windows.installer_args = vec![format!(
       "/D={}",
-      std::env::current_exe().unwrap().parent().unwrap().display()
+      tauri::utils::platform::current_exe()
+        .unwrap()
+        .parent()
+        .unwrap()
+        .display()
     )];
   }
   tauri::Builder::default()