"Import" menu sometimes disappears from sidebar

[tdonohue]

Describe the bug
After login as an Admin, the "Import" menu initially appears. However, if you select any other page in the sidebar, it disappears. Here's a screenshot... normally Import is right above Export.

Reproducible both locally & on http://demo7.dspace.org

To Reproduce
Steps to reproduce the behavior:

1. Login as an Admin
2. Look at sidebar. The Import menu should be there
3. Click on a different menu in sidebar, e.g. "Admin Search"
4. Look again at the sidebar, the Import menu will have disappeared.
5. If you click the reload button in your browser the Import menu will return. It will disappear again after you click a different item in the menu.

It almost seems like some sort of caching issue in the UI layer? Uncertain what could be causing this and why it's specific to the Import menu (no other menus are affected).

[tdonohue]

@artlowel : Would you or someone on your team have time to glance at this prior to 7.3? (Feel free to reassign internally, or let me know if you need me to find a different volunteer.)

[tdonohue]

Reassigning to myself... I've figured out the issue. The import menu had slightly outdated code. Updating it to match the export menu causes it to behave correctly. PR coming soon