Upgrade Underscore to 1.13.1

[chris-allan]

Upgrade Underscore to the latest 1.13.1 version. Current use is unaffected by the changelog and isolated to the following functions:

• _.each
• _.template
• _.uniq
• _.escape
• _.debounce

[will-moore]

Testing on merge-ci as well as merged locally, testing all the right-hand annotation panels where this is used extensively reveals no issues. LGTM 👍

[jburel]

Thanks, Merging so it is included in the 5.10.0 rc