[Dashboard] Browser Back Button Duplicates new Visualization Wizard

[ThomThomson]

Kibana version: Reproduced in master, 7.10, & 7.9.2

Describe the bug:

Steps to reproduce:

1. Open a new or existing dashboard
2. Hit the create new button
3. Press the browser back button a few times.
4. See that the wizard has been duplicated.

Expected behavior:
The browser back button should go back to the previous page and close the modal.