Set clearLogs accelerator for log-rendering plugins

Summary:
Sets a default key binding of `ctrl+l` to clear the screen within built-in Flipper plugins which display a log view.

Motivation: A small quality of life improvement for developers used to the default "clear screen" binding. This makes our log-rendering plugins consistent with other native apps such as terminals, Chrome DevTools, and many others.

Reviewed By: mweststrate

Differential Revision: D37782638

fbshipit-source-id: 0a85b930faaa0e9468d5391f15092aad7b6057ee

desktop/plugins/public/network/index.tsx

@@ -148,6 +148,7 @@ export function plugin(client: PluginClient<Events, Methods>) {
   client.addMenuEntry({
     action: 'clear',
     handler: clearLogs,
+    accelerator: 'ctrl+l',
   });
 
   client.onConnect(() => {