test: replace (webContents as any).destroy() with webContents.destroy() (#36653)

Co-authored-by: Milan Burda <miburda@microsoft.com>
Co-authored-by: John Kleinschmidt <jkleinsc@electronjs.org>

spec/api-ipc-renderer-spec.ts

@@ -144,7 +144,7 @@ describe('ipcRenderer module', () => {
         });
 
         after(() => {
-          (contents as any).destroy();
+          contents.destroy();
           contents = null as unknown as WebContents;
         });