fix: set native menus per-window (#8444)

Previously when a new window was created `Menu.setApplicationMenu()` was
called, which would change all windows' native menu to the newly created
one - causing every window menu to reference the newly created
`BrowserWindow`.

Now each window is set their own `Menu` instance which will have their
own `BrowserWindow`.

packages/insomnia/src/main/window-utils.ts

@@ -699,7 +699,7 @@ export function createWindow({ firstLaunch }: { firstLaunch?: boolean } = {}): E
     template.push(developerMenu);
   }
 
-  Menu.setApplicationMenu(Menu.buildFromTemplate(template));
+  mainBrowserWindow.setMenu(Menu.buildFromTemplate(template));
   return mainBrowserWindow;
 }