Found while investigating #25021

ElectronBrowserMainParts has a periodic timer that is used to trigger GC once a minute even on an idle system. While one wakeup per minute isn't bad, it's also been in there [since 2014](https://github.com/electron/electron/commit/4dd78480846557370dd53789d50e6cb0d6a81bcd) and may or may not still be necessary. It might be worth seeing what happens to memory overhead if this is disabled and/or triggered with a different mechanism.

```c++
  // Start idle gc.
  gc_timer_.Start(
      FROM_HERE, base::TimeDelta::FromMinutes(1),
      base::Bind(&v8::Isolate::LowMemoryNotification,
                 base::Unretained(js_env_->isolate())));
```


shell/browser/electron_browser_main_parts.h
void ToolkitInitialized() override;
  void PreMainMessageLoopRun() override;
  bool MainMessageLoopRun(int* result_code) override;
  void PreDefaultMainMessageLoopRun(base::OnceClosure quit_closure) override;
  void PostMainMessageLoopStart() override;
  void PostMainMessageLoopRun() override;
  void PreMainMessageLoopStart() override;
  void PostCreateThreads() override;
  void PostDestroyThreads() override;
 private:
  void PreMainMessageLoopStartCommon();
#if defined(OS_POSIX)
  
  void HandleSIGCHLD();
  void HandleShutdownSignals();
#endif
#if defined(OS_MAC)
  void FreeAppDelegate();
  void RegisterURLHandler();
  void InitializeMainNib();
#endif
#if defined(OS_MAC)
  std::unique_ptr<ViewsDelegateMac> views_delegate_;
#else
  std::unique_ptr<ViewsDelegate> views_delegate_;
#endif
#if defined(USE_AURA)
  std::unique_ptr<wm::WMState> wm_state_;
#endif
#if defined(USE_X11)