[BUG]: Comment upvotes do not persist on page refresh

### What happened?

A user contacted User Help and reporteded that the upvote feature on comments is not working as expected. When attempting to upvote a comment:

- The count temporarily increases.
- On refreshing the page, the upvote no longer shows and the count goes back to prior count.

I was able to replicate this issue on macOS Sonoma 14.3.1 in both:

- Chrome Version 136.0.7103.93
- Safari Version 17.3.1 (19617.2.4.11.12)

Interestingly, some comments have upvotes despite being able to replicate this - suggesting it is affecting a subset of users based on browser and/or OS (or a combo of both).

### Where is this happening?

The user specifically reported the issue happening on Crosswords comments, but it appears to happen across all articles with comments enabled (both those open and closed for comment). Screen recording here: https://drive.google.com/drive/folders/1KMDVioOYx5nLewy_YtII_BHL9YJoIvXR

### What is the impact?

Not all users can engage with comments; it is likely to lead to repeated attempts amongst users who pick up on this issue and cause frustration. Comments are only available on a limited number of articles, and even fewer engage with the comments section, so the overall number of users affected is likely to be fairly small.