Allow "duration" to be sent to the webview, to allow auto-increase project duration / auto resize the timeline

Author: jonoomph

src/windows/views/webview.py

@@ -220,7 +220,7 @@ def changed(self, action):
             return
 
         # Bail out if change unrelated to webview
-        if action.key and action.key[0] not in ["clips", "effects"]:
+        if action.key and action.key[0] not in ["clips", "effects", "duration"]:
             log.debug(f"Skipping unneeded webview update for '{action.key[0]}'")
             return