fix the memory leak every time the repo item menu is popped
fix the memory leak every time the repo item menu is popped

- this will recover approx. 2KiB memory every time

haiwen/seafile-client,wgaalves/seafile-client,losingle/seafile-client,daodaoliang/seafile-client,lucius-feng/seafile-client,wgaalves/seafile-client,losingle/seafile-client,wgaalves/seafile-client,haiwen/seafile-client,lucius-feng/seafile-client,daodaoliang/seafile-client,daodaoliang/seafile-client,losingle/seafile-client,wgaalves/seafile-client,haiwen/seafile-client,daodaoliang/seafile-client,haiwen/seafile-client,lucius-feng/seafile-client,lucius-feng/seafile-client,losingle/seafile-client