fix: truncate observable token size

[Junjiequan]

Description

Show token partially for security reason.

Tests included/Docs Updated?

• [ ] Included for each change/fix?
• [ ] Passing? (Merge will not be approved unless this is checked)
• [ ] Docs updated?
• [ ] New packages used/requires npm install?
• [ ] Toggle added for new features?
• [ ] Requires update of SciCat backend API?