[APPS-1291][BUG] Multi-location modals visibility

:koala::bug::+1:

Fixes a bug, in which toggling between locations, and launching a modal, would not open the modal in the second location (as documented in the JIRA task).

There is still an underlying issue with multi-location modals that will need to be addressed.

- [Jira](https://zendesk.atlassian.net/browse/APPS-1291)

/cc @zendesk/quokka