feat(permissions): Add idle-detection permission (#6438)

Added `idle-detection` permission needed to test IdleDetector:
* [CL 2417779 idle-detection: Implement requestPermission() method](https://chromium-review.googlesource.com/c/chromium/src/+/2417779)

src/common/Browser.ts

@@ -672,6 +672,7 @@ export class BrowserContext extends EventEmitter {
       ['clipboard-read', 'clipboardReadWrite'],
       ['clipboard-write', 'clipboardReadWrite'],
       ['payment-handler', 'paymentHandler'],
+      ['idle-detection', 'idleDetection'],
       // chrome-specific permissions we have.
       ['midi-sysex', 'midiSysex'],
     ]);