Fix JCB -> omero.lifesci.dundee.ac.uk links in demo 1.json

[will-moore]

See https://github.com/ome/omero-figure/pull/326 - Ported fixes on that PR to the gh-pages-staging branch as required to release as described at https://docs.openmicroscopy.org/contributing/ci-docs.html#term-figure-help-staging

To test:

• See https://figure.staging.openmicroscopy.org/demo/#file/1
• Figure should display as normal (images loading etc) and can be edited (change rendering settings etc)

[pwalczysko]

tested:

• labels
• cropping
• z slider
• rnd settings
• resize, snap to grid
• legend
• rotation
• ROI drawing

All looks fine. Good to merge FMPOV

[jburel]

Figure looks good. Merging