docs: correct `powerSaveBlocker.stop(id)` return type (#39320)

doc: correct powerSaveBlocker.stop return type

docs/api/power-save-blocker.md

@@ -49,6 +49,8 @@ is used.
 
 Stops the specified power save blocker.
 
+Returns `boolean` - Whether the specified `powerSaveBlocker` has been stopped.
+
 ### `powerSaveBlocker.isStarted(id)`
 
 * `id` Integer - The power save blocker id returned by `powerSaveBlocker.start`.

spec/ts-smoke/electron/main.ts

@@ -904,7 +904,8 @@ app.whenReady().then(() => {
 const id = powerSaveBlocker.start('prevent-display-sleep');
 console.log(powerSaveBlocker.isStarted(id));
 
-powerSaveBlocker.stop(id);
+const stopped = powerSaveBlocker.stop(id);
+console.log(`The powerSaveBlocker is ${stopped ? 'stopped' : 'not stopped'}`);
 
 // protocol
 // https://github.com/electron/electron/blob/main/docs/api/protocol.md