Image link hash bug 12304

Fixes https://trac.openmicroscopy.org.uk/ome/ticket/12304.

To test, open image viewer and either click the "Show ROIs" link or manually add a ```#``` to the end of the url. Then click "Image Link" and check that the link is valid (works when copied and pasted into browser). Check the url doesn't have the imageId duplicated: E.g. ```...img_detail/<imageId>/#/<imageId>/?c=...```