fix(external-api) add policy to support the Compute Pressure API

https://w3c.github.io/compute-pressure/#policy-control

modules/API/external/external_api.js

         const frameName = `jitsiConferenceFrame${id}`;
 
         this._frame = document.createElement('iframe');
-        this._frame.allow = 'camera; microphone; display-capture; autoplay; clipboard-write; hid; screen-wake-lock';
+        this._frame.allow = [
+            'autoplay',
+            'camera',
+            'clipboard-write',
+            'compute-pressure',
+            'display-capture',
+            'hid',
+            'microphone',
+            'screen-wake-lock'
+        ].join('; ');
         this._frame.name = frameName;
         this._frame.id = frameName;
         this._setSize(height, width);