[BUG] Incorrect singular form of "upvote" on feature page

**Describe the bug**
A feature with 1 upvote shows a label of "1 Upvotes"

**To Reproduce**
Steps to reproduce the behavior:

1. Go to a feature with 1 upvote, like https://webstatus.dev/features/text-justify (liable to change)
2. Look at the upvote link below the heading

**Expected behavior**
Should say "1 Upvote"

Alternatively, maybe lowercase would be more natural: "1 upvote"

**Screenshots**

Open the feature page at https://webstatus.dev/features/text-justify and reproduce the label with exactly one upvote, then trace the feature-page implementation that renders it. Done means the label uses the singular "Upvote" (or the agreed lowercase form) for one vote while preserving correct plural behavior.

Written by the indexing model from the issue text.