fix: temporary fix for running electron tests (#6576)

a workaround for spawn EINVAL error.
Found this issue according to https://github.com/node-red/node-red/pull/4652

~~In our case the electron app is spawned by playwright. I am still investigating the issue but don't know how long it takes.~~

Upstream fix: https://github.com/microsoft/playwright/pull/30382

packages/frontend/electron/scripts/dev.ts

@@ -37,6 +37,7 @@ function spawnOrReloadElectron() {
   spawnProcess = spawn(exe, ['.'], {
     cwd: electronDir,
     env: process.env,
+    shell: true,
   });
 
   spawnProcess.stdout.on('data', d => {